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The metallo-β-lactamase fold is the most abundant metal-binding domain found in two major kingdoms: bacteria and archaea. Despite the rapid growth in genomic information, most of these enzymes, which may play critical roles in cellular metabolism, remain uncharacterized in terms of structure and function. In this study, X-ray crystal structures of SAV1707, a hypothetical metalloenzyme from Staphylococcus aureus, and its complex with cAMP are reported at high resolutions of 2.05 and 1.55 Å, respectively, with a detailed atomic description. Through a functional study, it was verified that SAV1707 has Ni2+-dependent phosphodiesterase activity and Mn2+-dependent endonuclease activity, revealing a different metal selectivity depending on the reaction. In addition, the crystal structure of cAMP-bound SAV1707 shows a unique snapshot of cAMP that reveals the binding mode of the intermediate, and a key residue Phe511 that forms π–π interactions with cAMP was verified as contributing to substrate recognition by functional studies of its mutant. Overall, these findings characterized the relationship between the structure and function of SAV1707 and may provide further understanding of metalloenzymes possessing the metallo-β-lactamase fold.

A simple way to control the gate dielectric properties of vinyl-addition polynorbornene copolymers bearing pendant vinyl groups (P(NB/VNB)) through thiol–ene click chemistry is reported. The optimized content ratio of tetra-thiol cross-linkers leads to the enhanced gate dielectric properties and performance of organic field-effect transistors. Also, this approach provides photo-patternability, low-temperature solution-processing, and air-processability.

We isolated and purified an antimicrobial peptide (AMP) from the mantle of the hard-shelled mussel, Mytilus coruscus. The peptide was purified through C18 reversed-phase high-performance liquid chromatography, and displayed antibacterial activity. Total molecular mass of 11,182 Da was determined using matrix-assisted laser desorption ionization time-of-flight mass spectrophotometry. The N-terminal 23-amino acid sequence of its purified peak was obtained through Edman degradation, revealing 82% identity with myticusin-1 of M. coruscus. Complete sequence of the target peptide was determined through cDNA cloning and rapid amplification of cDNA ends. The complete sequence comprised 574 bp with a 387-bp open reading frame (ORF) encoding 24 amino acids of a signal peptide and 104 amino acids of a mature peptide, which was named myticusin-beta. Furthermore, we discovered two novel isoforms of myticusin-beta. We constructed and expressed recombinant myticusin-beta, which displayed antimicrobial activity against gram-positive (Bacillus cereus, Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, Streptococcus iniae, Streptococcus mutans) and gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Vibrio alginolyticus, Klebsiella pneumoniae). Purified recombinant myticusin-beta also showed anti-parasitic activity at various concentrations. A short AMP analog was designed and synthesized based on the sequence of myticusin-beta, with markedly improved antimicrobial activity. Expression of myticusin-beta was detected in the mantle at the highest level, followed by hemocytes. The results obtained in this work suggest that myticusin-beta is an immune-related AMP of M. coruscus and an effective alternative to antibiotics.

A Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strain, MYP1-1T, was isolated from the intestine of a stalked sea squirt (Styela clava) of the South Sea in the Republic of Korea. The neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain MYP1-1T clustered with the type strains of Halocynthiibacter species and Pseudohalocynthiibacter aestuariivivens . Strain MYP1-1T exhibited 16S rRNA gene sequence similarity values of 97.0–97.6 % to the type strains of Halocynthiibacter namhaensis , Halocynthiibacter arcticus and P. aestuariivivens . The phylogenetic tree based on genomic sequences showed that strain MYP1-1T formed a distinct branch separating it from the type strains of two Halocynthiibacter species and P. aestuariivivens and other taxa. The DNA G+C content of strain MYP1-1T from its genomic sequence was 55.0 mol%. Strain MYP1-1T contained Q-10 as the predominant ubiquinone and C18 : 1 ω7c as the major fatty acid. The major polar lipids of strain MYP1-1T were phosphatidylcholine, phosphatidylglycerol, one unidentified lipid and one unidentified aminolipid. The differences in fatty acid and polar lipid profiles and other differential phenotypic properties made it reasonable to distinguish strain MYP1-1T from the genera Halocynthiibacter and Pseudohalocynthiibacter . On the basis of the polyphasic taxonomic investigations, we conclude that strain MYP1-1T constitutes a new genus and species within the class Alphaproteobacteria , for which the name Paenihalocynthiibacter styelae gen. nov., sp. nov. is proposed. The type strain is MYP1-1T (=KCTC 82143T=NBRC 114355T).

American oyster defensin (AOD) was previously purified from acidified gill extract of the American oyster, Crassostrea virginica. AOD is composed of 38 amino acids with three disulfide bonds and exhibits strong antimicrobial activity against Gram-positive bacteria as well as significant activity against Gram-negative bacteria. Here, to develop promising peptides into antibiotic candidates, we designed five arginine-rich analogs (A0, A1, A2, A3, and A4), predicted their loop and extended strand/random structures—including nine amino acids and a disulfide bond derived from the C-terminus of AOD—and described their antimicrobial and cytotoxic effects, as well as their modes of action. In our experimental results, the A3 and A4 analogs exhibited potent antimicrobial activity against all test organisms—including four Gram-positive bacteria, six Gram-negative bacteria, and Candida albicans—without cell toxicity. A sequence of experiments, including a membrane permeabilization assay, DNA binding study, and DNA polymerization inhibition test, indicated that the two analogs (A3 and A4) possibly&nbsp, did not act directly on the bacterial membrane but instead interacted with intracellular components such as DNA or DNA amplification reactions. AOD analogs also showed strong bacterial inhibition activity in the plasma environment. In addition, analog-treated microbial cells clearly exhibited membrane disruption, damage, and leakage of cytoplasmic contents. Collectively, our results suggest that two analogs, A3 and A4, have potent antimicrobial activity via DNA interaction and have the potential for development into novel antimicrobial agents.

Anti-lipopolysaccharide factors (ALFs) are a representative host defense protein in crustaceans. In this study, we successfully developed two novel antimicrobial peptides (AMPs), named crab-ALF2A and crab-ALF6A, which contain changes to the amino acid sequences of the lipopolysaccharide binding domain and signal peptide, respectively, of the ALF of the swimming crab Portunus trituberculatus. The crab-ALF2A peptide showed potent antimicrobial activity against the Gram-positive bacteria Bacillus cereus, Staphylococcus aureus, and Streptococcus iniae (minimal effective concentration [MEC] 1.51–1.93 μg/mL) and the Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli (MEC 1.87–1.98 μg/mL), with maximal bactericidal activity at a peptide concentration of 5 μg/mL. The crab-ALF6A peptide also showed potent antimicrobial activity against B. cereus, S. aureus, and S. iniae (MEC 1.49–2.3 μg/mL) and P. aeruginosa and E. coli (MEC 1.72–1.19 μg/mL) at a peptide concentration of 5 μg/mL. Notably, the crab-ALF2A and crab-ALF6A peptides exhibited strong activity against Candida albicans (MECs of 2.11 and 1.95 μg/mL, respectively). These activities were stable following heat treatment. Moreover, the effect of crab-ALF2A and crab-ALF6A peptide treatment on microbe cell morphology was confirmed by scanning electron microscopy. Membrane disruption and damage, and the leakage of cytoplasmic content were clearly observed. A downsizing peptide approach illustrated that the hexapeptide ALF6A8 (RVLLRL) was the shortest peptide showing significant antimicrobial activity. Our approach allows for the generation of novel antimicrobial peptides in a cost effective manner as potential next-generation antibiotics.

Biomimetic polymeric materials, adopting the basic molecular design principles of biological materials, have been extensively studied in recent years but it is still challenging to combine assorted mechanical characteristics in a single material. Here, we present a simple and effective strategy to prepare mechanically robust yet resilient biomimetic polymer networks by utilizing dual noncovalent and covalent cross-linkings. Tailoring the dual cross-links consisting of thiourea noncovalent interactions and epoxy-amine covalent linkages in the biomimetic polymer networks enables a rare combination of excellent elastic modulus (1.1 GPa), yield stress (39 MPa), extensibility (320%), as well as complete strain and performance recovery after deformation at room temperature. The biomimetic polymer networks also exhibit highly adaptive mechanical properties in response to multiple-stimuli including strain rate, temperature, light, and solvent.

Acylphosphatase is the smallest enzyme that is widely distributed in many diverse organisms ranging from archaebacteria to higher-eukaryotes including the humans. The enzyme hydrolyzes the carboxyl-phosphate bonds of the acyl phosphates which are important intermediates in glycolysis, membrane pumps, tricarboxylic acid cycle, and urea biosynthesis. Despite its biological importance in critical cellular functions, very limited structural investigations have been conducted on bacterial acylphosphatases. Here, we first unveiled the crystal structure of SaAcP, an acylphosphatase from gram-positive S. aureus at the atomic level. Structural insights on the active site together with mutation study provided greater understanding of the catalytic mechanism of SaAcP as a bacterial acylphosphatase and as a putative apyrase. Furthermore, through NMR titration experiment of SaAcP in its solution state, the dynamics and the alterations of residues affected by the phosphate ion were validated. Our findings elucidate the structure-function relationship of acylphosphatases in gram-positive bacteria and will provide a valuable basis for researchers in the field related to bacterial acylphosphatases.

Two species of brown seaweeds, Saccharina japonica and Undaria pinnatifida were fermented by the red molds; Monascus purpureus and Monascus kaoliang to increase their bio-functional properties. The phenolic contents of S. japonica fermented by M. purpureus (SjMp) and M. kaoliang (SjMk) were the highest 71.53 ± 2.25 and 66.50 ± 4.64 mg gallic acid equivalent/g extract, respectively, whereas the highest flavonoid content was evident in S. japonica fermented by M. purpureus (SjMp) and U. pinnatifida fermented by M. purpureus (UpMp) (27.93 ± 0.28 and 26.88 ± 1.24 mg quercetin equivalent/g extract, respectively). Reducing sugar, protein and essential fatty acids levels also increased in fermented seaweeds. The antioxidant activities of fermented seaweed extracts exhibited significantly (p

Carboxylate-functionalized polymers of intrinsic microporosity (PIMs) are promising materials for gas separation application. However, highly carboxylate-functionalized PIMs (HCPIMs) have not been reported owing to overlooked intermediate products. Herein, we successfully prepared HCPIMs (∼92 mol % of carboxylic acid group) through a prolonged alkaline hydrolysis process (360 h). HCPIMs were found to be soluble in various organic solvents, such as tetrahydrofuran and dimethyl sulfoxide, and then free-standing HCPIM membranes could be prepared by the common solution casting method. The HCPIM membranes were found to have smaller interchain distances and higher CO2 affinity than original PIM-1 films. For example, small gas molecules, such as carbon dioxide, were effectively separated due to the enhanced diffusivity selectivity combined with the smaller cavity size. Further, strong interactions between carbon dioxide and the carboxylic acid groups increased solubility selectivity. These synergetic effects end...

In this work, we investigated the effects of the flow modifier addition on the rheological behavior and mechanical properties of high-filled polyamide 66 composites prepared from melt compounding. The flow modifiers were prepared from various amine monomers and fatty acids, and their structures were analyzed by Fourier transform infrared spectroscopy. The synthesized flow modifiers were added simultaneously during melt compounding. The presence of flow modifiers significantly reduced torque in neat polyamide 66 polymer and glass fiber-reinforced polyamide 66 composites, respectively, while the torque during compounding in composites with glass fiber contents of 50 wt% has decreased by approximately 12% after the addition of 1 phr of hexamethylene bis -stearamide indicating the simultaneous enhancement in flowability. The presence of the synthesized flow modifiers in matrix polymers improves flowability of the composites during injection molding without compromising the mechanical properties.

We purified an ∼6.4-kDa antimicrobial peptide from an acidified gill extract of the Pacific oyster, Crassostrea gigas , by cation-exchange and C 18 reversed-phase high performance liquid chromatography (HPLC). The identified peptide was composed of 54 amino acids and had a molecular weight of 6484.6 Da. Comparison of the amino acid sequence and molecular weight with those of other known proteins or peptides revealed that the peptide had high identity with the 60S ribosomal protein L29, and so was named cgRPL29. The full-length cgRPL29 cDNA of the Pacific oyster comprised 325-bp, including a 5'-untranslated region (UTR) of 100-bp, a 3′-UTR of 57-bp, and an open reading frame of 168-bp encoding 55 amino acids, with a Met residue at the N-terminus. The cgRPL29 mRNA tissue distribution suggested that it is constitutively expressed in a non-tissue-specific manner. Secondary structural prediction and homology modeling indicated cgRPL29 have an unordered structure containing two partial α-helical regions. This is to our knowledge the first report of the antimicrobial effect of the 60S ribosomal protein L29 from marine invertebrates.

NAD(P)-dependent steroid dehydrogenase-like (NSDHL), an essential enzyme in human cholesterol synthesis and a regulator of epidermal growth factor receptor (EGFR) trafficking pathways, has attracted interest as a therapeutic target due to its crucial relevance to cholesterol-related diseases and carcinomas. However, the development of pharmacological agents for targeting NSDHL has been hindered by the absence of the atomic details of NSDHL. In this study, we reported two X-ray crystal structures of human NSDHL, which revealed a detailed description of the coenzyme-binding site and the unique conformational change upon the binding of a coenzyme. A structure-based virtual screening and biochemical evaluation were performed and identified a novel inhibitor for NSDHL harboring suppressive activity towards EGFR. In EGFR-driven human cancer cells, treatment with the potent NSDHL inhibitor enhanced the antitumor effect of an EGFR kinase inhibitor. Overall, these findings could serve as good platforms for the development of therapeutic agents against NSDHL-related diseases.

In this study, graphite nanoplatelets (GNPs), known as a thermally conductive and anisotropic carbon material, was used with polyvinyl alcohol (PVA) as matrix, which is a hydrophilic and biodegradable polymer. In order to expect enhanced thermal conductivity, silver nanoparticle-decorated graphite nanoplatelets (Ag-GNPs) were fabricated by adding silver acetate as a precursor using ‘mix-and-heat’ method. Polyvinyl alcohol composite films containing pristine GNPs and Ag-GNPs were prepared using solution casting method. The prepared composite films were uniaxially stretched to induce the filler alignment along the stretching direction as well as the strain-induced crystallization in polymer chains. The effects of the particle size of GNPs, the silver nanoparticle on the surface of GNPs, and the stretching ratios on the thermal conductivity of the composite films were investigated.

Seaweeds have valuable pharmacological properties attributed to the presence of various bioactive compounds. In this study, the phytochemical composition and antioxidant activity of various crude extracts of Hypnea musciformis were determined. Phytochemical screening, Fourier transform infrared (FT-IR) and Gas chromatography-mass spectrometry (GC-MS) analysis were performed to identify the chemical composition of the crude extracts. Antioxidant activity was assayed by total antioxidant capacity for phosphomolybdenum, 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and reducing power (RP) assays. The various extracts contained terpenoid, saponin, phlobatannin, cardiac glycosides, phenolics and flavonoids at varying concentrations. FT-IR results confirmed the presence of phenols, carboxylic acid, ketones, ethers, aromatics, amides and sulfonates. GC-MS of organic extracts showed that the extracts contain numerous high and low molecular weight compounds. Methanol extract showed the highest phenolic content and antioxidant activity measured by different assays such as phosphomolybdenum (8.2 mg ascorbic acid equivalent), DPPH (79.34%), ABTS (80.21%) and RP (2.36 absorbance at 700 nm) followed by butanol, chloroform and ethyl acetate. Furthermore, methanol and butanol extracts inhibited radical-induced DNA damage. Practical Applications Hypnea musciformis is widely known source for carrageenan but phytochemical composition and functional activities of this seaweed have not been well studied. Extraction of functional compound depends on solvent and method employed. Results found that the extract showed the presence of diversified phytochemical composition with its potent antioxidant activity at varying degrees. Our results can be used in the future to identify, isolate and characterize the specific compounds responsible for antioxidant activity.

We isolated and characterised a cDNA encoding the aspartic protease cathepsin E (CTSE) in Korean rose bitterling, Rhodeus uyekii. The full-length Rhodeus uyekii CTSE (RuCTSE) cDNA (1396 bp) contains an open reading frame of 1218 bp, encoding 405 amino acids. Alignment of multiple CTSE protein sequences revealed that two of the aspartyl protease active site residues and a disulphide bond were well-conserved among the other CTSE sequences. Phylogenetic analysis revealed that RuCTSE is most closely related to freshwater fish cathepsin E. RuCTSE is widely expressed in the liver, spleen, ovary, testis, brain, eye, intestine, muscle, fin, stomach, and kidney. This first report of teleost CTSE will provide important information related to the identification of other cathepsin E genes in various fish species and will serve as a useful molecular tool to help clarify biological activities in other teleosts.

An antimicrobial peptide with 55 amino acid residues was purified by C18 reversed-phase high-performance liquid chromatography (HPLC) from foot extract of the hard-shelled mussel, Mytilus coruscus. This peptide showed strong antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as fungi. The purified peptide was determined to have a molecular mass of 6202 Da by matrix-assisted laser desorption/ionization time-of-flight mass spectrophotometry (MALDI-TOF/MS). The identified 20-amino acid sequence of the purified peak by Edman degradation shared 100% identity with the N-terminal regions of mytichitin-1, mytichitin-2, mytichitin-3, mytichitin-4, mytichitin-5, and chitinase-like protein-1, and so was named mytichitin-CBD. The cDNA of mytichitin-CBD was cloned and sequenced by rapid amplification of cDNA ends (RACE). The mRNA transcripts were mainly detected in foot tissue, and they were up-regulated and peaked at 4 h after bacterial infection. We constructed and expressed recombinant mytichitin-CBD protein which displayed antimicrobial activity against Gram-negative bacteria Gram-positive bacteria and the fungus as well as anti-parasitic activity against scuticociliates. The results of this study demonstrate that the peptide isolated from M. coruscus is related to the innate immune system of this marine invertebrate and is a possible alternative to antibiotics.

A 5.6 kDa antimicrobial peptide (AMP) was purified from acidified gill extract of the pen shell, Atrina pectinata, by cation exchange and C18 reversed-phase high performance liquid chromatography. Comparison of the amino acid sequences and molecular weight of this peptide with those of other known AMPs revealed that it had high sequence homology with that of cgMolluscidin or hdMolluscidin; it was designated apMolluscidin. apMolluscidin comprises 59 amino acid residues containing several dibasic residue repeats and sequence repeats such as Lys-Lys and Lys-Gly. apMolluscidin exhibited potent antimicrobial activity against both Gram-positive bacteria including Bacillus subtilis (minimal effective concentration [MEC], 2.1 μg/mL), and Gram-negative bacteria including E. coli D31 (MEC, 0.5 μg/mL), without hemolytic activity. However, it did not show any activity against fungi such as Candida albicans. Secondary structure prediction suggested that it might form two helical regions and have an amphipathic structure. Full-length apMolluscidin cDNA contained 812 base pairs (bp), including a 5′-untranslated region (UTR) of 82 bp, a 3′-UTR of 547 bp, and a coding sequence of 183 bp encoding 60 amino acids (containing Met). Furthermore, qPCR analyses revealed that the mature peptide translated from apMolluscidin mRNA is expressed in a tissue-specific manner in locations such as the gill and siphon. These results indicate that apMolluscidin might be related to the innate immune defense system of abalone and may not act directly on the bacterial membrane. This is the first report of an AMP from the pen shell with a fully identified amino acid sequence.

Oxidative stresses, such as reactive oxygen species, reactive electrophilic species, reactive nitrogen species, and reactive chlorine species, can damage cellular components, leading to cellular malfunction and death. In response to oxidative stress, bacteria have evolved redox-responsive sensors that enable them to simultaneously monitor and eradicate potential oxidative stress. Specifically, redox-sensing transcription regulators react to oxidative stress by means of modifying the thiol groups of cysteine residues, functioning as part of an efficient survival mechanism for many bacteria. In general, oxidative molecules can induce changes in the three-dimensional structures of redox sensors, which, in turn, affects the transcription of specific genes in detoxification pathways and defense mechanisms. Moreover, pathogenic bacteria utilize these redox sensors for adaptation and to evade subsequent oxidative attacks from host immune defense. For this reason, the redox sensors of pathogenic bacteria are potential antibiotic targets. Understanding the regulatory mechanisms of thiol-based redox sensors in bacteria will provide insight and knowledge into the discovery of new antibiotics.

Vinyl addition polymers of substituted norbornene (NB) monomers possess very high glass-transition temperatures, making them useful in diverse applications; however, until very recently, the lack of an applicable living polymerization chemistry has precluded the synthesis of such polymers with controlled architecture, or copolymers with controlled sequence distribution. In the present work, block and random copolymers of NB monomers bearing hydroxyhexafluoroisopropyl and n-butyl substituents (HFANB and BuNB) are synthesized via living vinyl addition polymerization, using (η3-allyl)Pd(i-Pr3P)Cl activated by [Li(OEt2)2.5]B(C6F5)4 as the initiator. Both series of polymers are cast into the selective skin layers of thin film composite (TFC) membranes, and these organophilic membranes are investigated for the concentration of n-butanol from dilute aqueous solution via pervaporation. The block copolymers show well-defined microphase-separated morphologies, both in bulk and as the selective skin layers on TFC me...

Thioredoxin is a multifunctional antioxidant enzyme that belongs to the reductase family. In this study, we cloned and characterized thioredoxin 1 cDNA from the Korean rose bitterling Rhodeus uyekii (RuTrx). The full-length RuTrx cDNA consists of 674 bp with a 324 nt open reading frame (ORF) encoding a 107 aa protein. The deduced RuTrx amino acid sequence indicated a characteristic redox active site, (31)WCGPC(35). Pairwise alignment revealed RuTrx amino acid identity (55.1%-83.2%) with orthologs from various species of mammalia, amphibia, fish and bird. Phylogenetic analysis was conducted to determine the evolutionary position of RuTrx. Expression analysis showed that RuTrx transcripts were present in all of the tissues examined, and was high in the hepatopancreas of R. uyekii. During early development, the expression of RuTrx transcripts was increased. Recombinant RuTrx protein (rRuTrx) was tested for its capacity to serve as an antioxidant enzyme using a metal-catalyzed oxidation (MCO) system. The ability of rRuTrx to protect against supercoiled DNA cleavage due to oxidative nicking increased in a dose-dependent manner. In Raw264.7 cells, Dihydroethidium (DHE) staining for ROS production indicated the antioxidant activity of rRuTrx. Together, these findings suggest that RuTrx may play a role in maintaining the redox state balance in Korean rose bitterling R. uyekii.

Core-shell silica particles with ion-conducting poly(ethylene glycol) and anion-trapping boron moiety in the shell layer were prepared to be used as fillers for polymer composite electrolytes based on organic/inorganic hybrid branched copolymer as polymer matrix for all-solid-state lithium-ion battery applications. The core-shell silica particles were found to improve mechanical strength and thermal stability of the polymer matrix and poly(ethylene glycol) and boron moiety in the shell layer increase compatibility between filler and polymer matrix. Furthermore, boron moiety in the shell layer increases both ionic conductivity and lithium transference number of the polymer matrix because lithium salt can be more easily dissociated by the anion-trapping boron. Interfacial compatibility with lithium metal anode is also improved because well-dispersed silica particles serve as protective layer against interfacial side reactions. As a result, all-solid-state battery performance was found to be enhanced when the copolymer having core-shell silica particles with the boron moiety was used as solid polymer electrolyte.

The vinyl addition polymerization of substituted norbornene (NB) monomers, via (t-Bu3P)PdMeCl activated by [Li(OEt2)2.5]B(C6F5)4, is investigated. NB monomers bearing alkyl, aryl, fluoroaryl, and even hexafluoroisopropanol substituents yield polymers exhibiting monomodal and narrow molecular weight distributions, with molecular weight controlled by reaction time and monomer to initiator ratio, demonstrating the living nature of these polymerizations. These polymers are soluble in common organic solvents and possess excellent thermal stability. Block copolymers are also prepared via sequential monomer addition; these are the first examples of well-defined block copolymers of substituted NB monomers enchained by vinyl addition polymerization.

Among the various human growth factors, epidermal growth factor (hEGF, consisting of 53 amino acids) has various effects on cell regeneration, stimulation of proliferation, migration of keratinocytes, formation of granulation tissues, and stimulation of fibroblast motility, which are important for wound healing. Owing to their multiple activities, EGFs are used as pharmaceutical and cosmetic agents. However, their low productivity, limited target specificity, and short half-life inhibit their application as therapeutic agents. To overcome these obstacles, we fused the collagen-binding domain (CBD) of Vibrio mimicus metalloprotease to EGF protein. About 18 or 12 amino acids (aa) (of the 33 total amino acids), which were essential for collagen-binding activity, were combined with the N- and C-termini of EGF. We constructed, expressed, and purified EGF (53 aa)-CBD (18 aa), EGF (53 aa)-CBD (12 aa), CBD (18 aa)-EGF (53 aa), and CBD (12 aa)-EGF (53 aa). These purified recombinant proteins increased the numbers of cells in treated specimens compared with non-treated specimens and control hEGF samples. The collagen-binding activities were also evaluated. Furthermore, CBD-hybridized hEGF induced phosphorylation of the EGF receptor. These results suggested that these fusion proteins could be applicable as small therapeutic agents in wound tissue healing.

A series of poly(methyl methacrylate) derivatives containing polyhedral oligomeric silsesquioxane (POSS) groups (MCP#) were synthesised via free radical polymerisation (FRP) using methacryl isobutyl POSS (MA-POSS) and methyl methacrylate as monomers to investigate liquid crystal (LC) alignment property of these polymer films. The LC cells made from the films of the polymers having 100 mol% of MA-POSS units (MCP100) showed vertical LC alignment having a pretilt angle of about 90°. The vertical LC alignment behaviour on the MCP100 film was ascribed to the very hydrophobic MCP100 surface having the surface energy value smaller than about 23 mJ/m2 generated by the nonpolar bulky POSS group. Good electro-optical characteristics, such as voltage holding ratio (VHR) and residual DC voltage (R-DC), were observed for the LC cells fabricated using MCP100 as a LC alignment layer.

We describe the antimicrobial function of peptides derived from the C-terminus of the olive flounder LBP BPI precursor protein. The investigated peptides, namely, ofLBP1N, ofLBP2A, ofLBP4N, ofLBP5A, and ofLBP6A, formed α-helical structures, showing significant antimicrobial activity against several Gram-negative bacteria, Gram-positive bacteria, and the yeast Candida albicans, but very limited hemolytic activities. The biological activities of these five analogs were evaluated against biomembranes or artificial membranes for the development of candidate therapeutic agents. Gel retardation studies revealed that peptides bound to DNA and inhibited migration on an agarose gel. In addition, we demonstrated that ofLBP6A inhibited polymerase chain reaction. These results suggested that the ofLBP-derived peptide bactericidal mechanism may be related to the interaction with intracellular components such as DNA or polymerase.

Screening of a gene library from Paenibacillus sp. PBS-2 generated in Escherichia coli led to the identification of a clone with lipolytic activity. Sequence analysis showed an open reading frame encoding a polypeptide of 378 amino acid residues with a predicted molecular mass of 42 kDa. The esterase displayed 69% and 42% identity with the putative β-lactamases from Paenibacillus sp. JDR-2 and Clostridium sp. BNL1100, respectively. The esterase contained a Serx- x-Lys motif that is conserved among all β-lactamases found to date. The protein PBS-2 was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at 18°C. The enzyme is a serine protein and was active against p-nitrophenyl esters of C2, C4, C8, and C10. The optimum pH and temperature for enzyme activity were pH 9.0 and 30°C, respectively. Relative activity of 55% remained at up to 5°C with an activation energy of 5.84 kcal/mol, which indicates that the enzyme is cold-adapted. Enzyme activity was inhibited by Cd(2+), Cu(2+), and Hg(2+) ions. As expected for a serine esterase, activity was inhibited by phenylmethylsulfonyl fluoride. The enzyme was remarkably active and stable in the presence of commercial detergents and organic solvents. This cold-adapted esterase has potential as a biocatalyst and detergent additive for use at low temperatures.

Vibrio anguillarum, a causative agent of vibriosis in finfish, crustaceans, and bivalves, is a Gram-negative, motile marine bacterium. Most bacteria have developed survival strategies in various environments. The aim of this study was to investigate the changes in protein expression of V. anguillarum O1 incubated under different conditions using two dimensional electrophoresis and MALDI-TOF MS/MS analysis. Result indicated that peptidyl-prolyl cis/trans isomerase (PPIase) expression was increasingly appeared when incubated at low temperature (15°C) and alkaline conditions (pH 10). Subsequently, the ppi gene from V. anguillarum O1 was isolated and overexpressed in Escherichia coli to characterize the biochemical properties. The cloned ppi gene encoded 206 amino acids containing the conserved regions identified in FK506 binding pocket. To determine the optimal conditions of the purified recombinant PPIase protein (VaFKBP22), we used Succinyl-Ala-Phe-Pro-Phe-p nitroanilide as substrate and the highest enzymatic activity was found at 5°C and pH 6. VaFKBP22 was detected in the cytoplasm and periplasm of V. anguillarum O1. In addition, VaFKBP22 also showed chaperone activity and did not show cytotoxic activity.

We isolated a metalloprotease (MP) homologue from an abalone muscle cDNA library. A 3284-kb full-length cDNA encoding a predicted polypeptide of 667 amino acids was sequenced. The abalone MP Haliotis discus hannai (HdMP) exhibited a domain structure typical of the peptidase M4 family, a 21-amino acid N-terminal hydrophobic signal sequence followed by a long propeptide sequence of 347 amino acids and the mature protease domain comprising 299 amino acids. The mature region contains features characteristic of a zinc protease, including a zinc-binding motif (HEXXH) and an active site. The protein showed 32–38% amino acid sequence identity with other known MP sequences and with a hypothetical protein from owl limpet. The mRNA transcript is expressed in almost all tissues, with high expression in the mantle and adductor muscle of healthy abalones, and is expressed constitutively during the early developmental stages after fertilization. Lipopolysaccharide or poly I:C stimulation induced the expression of the Hd...

A series of composite polymer electrolytes were prepared using an organic/inorganic hybrid branched-graft copolymer (BCP) based on poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3-(3,5,7,9,11,13,15-heptaisobutylpentacyclo-[9.5.1.13,9.15,15.17,13]octasiloxane-1-yl)propyl methacrylate (MA-POSS) as the polymer matrix and poly(ethylene glycol)-grafted graphene oxide (PGO) as the filler material, and they were applied as solid-state polymer electrolytes (SPEs) for lithium-ion battery applications. The ionic conductivity of the composite polymer electrolyte containing 0.2 wt% of PGO (2.1 × 10−4 S cm−1 at 30 °C) was found to be one order of magnitude higher than that of the BCP (1.1 × 10−5 S cm−1 at 30 °C); the pristine polymer matrix, because of the larger amount of lithium salt, can be dissociated in the composite polymer electrolyte by Lewis acid–base interactions between the PGO and lithium salt. The thermal and mechanical stabilities of the composite polymer electrolytes were also improved by introducing PGO fillers and reasonable storage modulus values were maintained even at elevated temperatures up to 150 °C. All-solid-state battery performance was evaluated with the composite polymer electrolyte containing 0.2 wt% of PGO, resulting in superior cycle performance compared to that of the BCP due to the enhanced ionic conductivity as well as additional ion-conducting paths provided by the PGO fillers.

Polymers containing a renewable cardanol moiety were prepared via radical polymerization of 2-hydroxy-3-cardanylpropyl methacrylate (HCPM) and methyl methacrylate (MMA), where HCPM was synthesized by a reaction of cardanol with glycidyl methacrylate in the presence of a base catalyst. Incorporation of the cardanol moiety into PMMA was found to increase the thermal and mechanical stability of the brittle PMMA. When the cardanol based polymers were irradiated with UV light, the mechanical stability increased further because cross-linked networks were formed between the double bonds in the cardanol moieties. Cross-linked polymer films containing the cardanol moiety exhibited high gloss and transparency to visible light. Cardanol-containing polymers with and without the cross-linked networks and other cardanol-based polymers such as poly(cardanyl acrylate) and poly(2-acetoxy-3-cardanylpropyl methacrylate) all showed high antibacterial activity against Escherichia coli (E. coli), indicating that the disappearance of double bonds and/or the structure changes of connecting groups do not diminish the intrinsic bactericidal properties of the cardanol moieties.

A series of organic/inorganic hybrid branched (BCPs) and linear (LCPs)-graft copolymers comprising poly(ethylene glycol) methyl ether methacrylate (PEGMA), 3-(3,5,7,9,11,13,15-heptaisobutyl-pentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane-1-yl)propyl methacrylate (MA-POSS), and ethylene glycol dimethacrylate (EGDMA) were synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization for application to solid polymer electrolyte (SPE) materials in high-temperature lithium-ion batteries. Dimensionally stable free-standing films were obtained when the MA-POSS contents in BCPs and LCPs are larger than 21 mol% and maintained their original shape and storage modulus even if the temperature increases up to 90 °C. The maximum ionic conductivity value of the BCP electrolyte containing 21 mol% of MA-POSS was 1.6 × 10−4 S cm−1 at 60 °C and that of the LCP electrolyte containing 21 mol% of MA-POSS was 5.6 × 10−5 S cm−1 at 60 °C, indicating that the branched-graft copolymer electrolyte has higher ionic conductivity than the linear-graft counterpart, due to the increased chain mobility, as estimated by a smaller Tg value. All-solid-state batteries prepared using the BCP electrolyte showed a reasonable cell performance at 60 °C without causing safety problems, demonstrating great potential of BCPs as SPE materials for high-temperature battery systems.

Antimicrobial peptides are a pivotal component of the invertebrate innate immune system. In this study, we identified a lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) gene from the pacific abalone Haliotis discus hannai (HDH), which is involved in the pattern recognition mechanism and plays avital role in the defense mechanism of invertebrates immune system. The HDH-LGBP cDNA consisted of a 1263-bp open reading frame (ORF) encoding a polypeptide of 420 amino acids, with a 20-amino-acid signal sequence. The molecular mass of the protein portion was 45.5 kDa, and the predicted isoelectric point of the mature protein was 4.93. Characteristic potential polysaccharide binding motif, glucanase motif, and β-glucan recognition motif were identified in the LGBP of HDH. We used its polysaccharide-binding motif sequence to design two novel antimicrobial peptide analogs (HDH-LGBP-A1 and HDH-LGBP-A2). By substituting a positively charged amino acid and amidation at the C-terminus, the pI and net charge of the HDH-LGBP increased, and the proteins formed an α-helical structure. The HDH-LGBP analogs exhibited antibacterial and antifungal activity, with minimal effective concentrations ranging from 0.008 to 2.2 μg/mL. Additionally, both were toxic against human cervix (HeLa), lung (A549), and colon (HCT 116) carcinoma cell lines but not much on human umbilical vein cell (HUVEC). Fluorescence-activated cell sorter (FACS) analysis showed that HDH-LGBP analogs disturb the cancer cell membrane and cause apoptotic cell death. These results suggest the use of HDH-LGBP analogs as multifunctional drugs.

The gene encoding an esterase from Photobacterium sp. MA1-3 was cloned in Escherichia coli using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (948 bp) corresponded to a protein of 315 amino acid residues with a molecular weight of 35 kDa and a pI of 6.06. The deduced protein showed 74% and 68% amino acid sequence identities with the putative esterases from Photobacterium profundum SS9 and Photobacterium damselae, respectively. Absence of a signal peptide indicated that it was a cell-bound protein. Sequence analysis showed that the protein contained the signature G-X-S-X-G included in most serine-esterases and lipases. The MA1-3 esterase was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at 18°C. The enzyme was a serine-esterase and was active against C2, C4, C8 and C10 p-nitrophenyl esters. The optimum pH and temperature for enzyme activity were pH 8.0 and 30°C, respectively. Relative activity remained up to 45% even at 5°C with an activation energy of 7.69 kcal/mol, which indicated that it was a cold-adapted enzyme. Enzyme activity was inhibited by Cd 2+ , Cu 2+ , Zn 2+ , and Hg 2+ ions.

A Gram-stain-negative, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated P-MA1-7T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea, Korea. Strain P-MA1-7T grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2–3 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain P-MA1-7T fell within the cluster comprising the type strains of four species of the genus Litoreibacter , exhibiting 16S rRNA gene sequence similarity values of 97.0–98.5 % to these four type strains and less than 95.9 % sequence similarity to the strains of the other species examined. Strain P-MA1-7T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the predominant fatty acid. The major polar lipids of strain P-MA1-7T were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain P-MA1-7T was 58.3 mol% and DNA–DNA relatedness values of strain P-MA1-7T with the type strains of the four species of the genus Litoreibacter were in the range of 8–21 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain P-MA1-7T was separate from other species of the genus Litoreibacter . On the basis of these data, strain P-MA1-7T is considered to represent a novel species of the genus Litoreibacter , for which the name Litoreibacter halocynthiae sp. nov. is proposed. The type strain is P-MA1-7T ( = KCTC 32213T = CCUG 63416T).

A bacterial strain that produces a cold-adapted esterase was isolated from tidal flats and identified as Shewanella sp. Ke75. In the present study, the corresponding gene was cloned using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (957 bp) corresponded to a protein of 318 amino acid residues with a calculated molecular weight of 34875 Da. The esterase showed 68 and 57% identities with the putative esterases of Shewanella amazonensis SB2B and Colwellia psychrerythraea 34H, respectively. The esterase contained a putative leader sequence, as well as the conserved catalytic triad (Ser, His, Asp), consensus pentapeptide GXSXG, and oxyanion hole sequence (HG). The protein Ke75 was produced in both soluble and insoluble forms when Escherichia coli cells harboring the gene were cultured at 30°C. The enzyme showed specificity for C4 (butyrate) as a substrate, with little activity toward the other p-nitrophenyl esters tested. The optimum pH and temperature for enzyme activity were pH 9.0 and 30°C, respectively. Relative activity remained up to 60% even at 5°C with an activation energy of 6.29 kcal/mol, which indicated that it was a cold-adapted enzyme. Enzyme activity was enhanced in the presence of Mn2+ ions, but inhibited by Cd2+, Cu2+, Hg2+, and Zn2+ ions.

Amphiphilic organic/inorganic hybrid star-shaped polymers (SPP) were prepared by atom transfer radical polymerization (ATRP) using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3-(3,5,7,9,11,13,15-heptacyclohexyl-pentacyclo[9.5.1.1³,⁹.1⁵,¹⁵.1⁷,¹³]-octasiloxane-1-yl)propyl methacrylate (MA-POSS) as monomers and octakis(2-bromo-2-methylpropionoxypropyldimethylsiloxy)-octasilsesquioxane (OBPS) as an initiator. Star-shaped polymers (SPM) having PEGMA and methyl methacrylate (MMA) moieties were also prepared for comparative purposes. Polysulfone (PSf) ultrafiltration membranes coated with the SPP showed higher bio- and oil-fouling resistance and flux-recovery ability than the bare PSf membrane. Moreover, the SPP-coated membranes exhibited better antifouling properties than the SPM-coated membrane when they were used for oil/water emulsion filtration. The dual effective antifouling properties of the SPP were ascribed to the simultaneous enrichment of hydrophilic PEG and hydrophobic POSS moieties on the membrane surfaces resulting in the decrease in interactions with proteins and the increase in repellence to oils.

A series of branched polymers for chemically amplified resists (CARs) were prepared through the reversible addition–fragmentation chain-transfer (RAFT) copolymerization of three monomers with lithographic functionalities and an acid-cleavable dimethacrylate monomer. The three monomers with lithographic functionalities were 2-ethyl-2-adamantyl methacrylate, α-γ-butyrolactone methacrylate, and 3-hydroxy-1-adamantyl methacrylate. The acid-cleavable monomer was 2,5-dimethyl-2,5-hexanediol dimethacrylate (DMHDMA), and 2-cyanoprop-2-yl-1-dithionaphthalate was used as a chain-transfer agent. Because DMHDMA contains two methacrylate groups, it induced the branched structures of the polymers. The degree of branching could be controlled by the molar fraction of DMHDMA in the monomer mixtures. The size and structure of the polymers obtained after hydrolysis were very close to those of linear polymers prepared by RAFT copolymerization with the same amount of reagents, only without the acid-cleavable monomer. A preliminary lithography test using an argon fluoride source demonstrated that the acid-cleavable branched polymers could be promising candidates for CAR materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Cysteine-rich intestinal protein (CRIP) is a LIM domain protein containing a zinc-finger motif and plays a role in the regulation of the inflammatory immune response. In the present study, we isolated a CRIP1 cDNA, designated PoCRIP1, from an olive flounder Paralichthys olivaceus intestine cDNA library by EST analysis. The PoCRIP cDNA consists of 421 bp with a polyadenylation signal sequence, AATAAA, and a poly(A) tail; it encodes a polypeptide of 76 amino acids containing a double zinc-finger motif (Cys(2)HisCys and Cys(4) sequences). The deduced amino acid sequence of PoCRIP1 showed 75.3-94.7% homology with CRIP1s of other species, including mammals. The PoCRIP1 transcript was highly expressed in the intestine and pyloric ceca and moderately expressed in the gill, heart, kidney, liver, muscle, spleen, skin, and stomach of normal conditioned flounder. Inducible expression of the PoCRIP1 transcript was observed in flounder challenged with Edwardsiella tarda, an economically important pathogen for aquaculture of flounder. Over-expression of PoCRIP1 augmented p65-driven flounder IL-6 promoter activity in HINAE cells. These results suggest that PoCRIP1 may function in the immune response of the flounder through the regulation of cytokine expression.

Salinisphaera sp. P7-4 was isolated from the intestine of silver whiting, Sillago japonicas caught in the Pacific Ocean, and the esterase gene was cloned using the shotgun method. The amino acid sequence deduced from the nucleotide sequence (951 bp) corresponded to a protein of 316 amino acid residues with a molecular weight of 34,443. The esterase had 46 and 44% identities with the esterase enzymes of Ralstonia eutropha JMP134 and Rhodopseudomonas palustris HaA2, respectively. The primary structure of P7-4 esterase showed the conserved catalytic triad (Ser, Asp, His), consensus pentapeptide GXSXG, and oxyanion hole sequence (HG). The protein P7-4 was successfully expressed in Escherichia coli in a biologically active form. The enzyme showed high catalytic activity at low temperatures (5-25° C) with an activation energy of 2.18 kcal/mol. This result indicated that the esterase from Salinisphaera sp. P7-4 is a new cold-adapted enzyme. The enzyme preferentially hydrolyzed acyl-group chains with short chain lengths of ≤10 carbon. Metal ions such as Cd2(+), Co2(+), Cu2(+), Hg2(+), Ni2(+) and Zn2(+) inhibited enzymatic activity. Additionally, EDTA has no effect on its activity, whereas inhibition was observed with PMSF, a serine hydrolase inhibitor.

Solid polymer electrolytes (SPEs) for all-solid-state lithium-ion batteries are prepared by simple one-pot polymerization induced by ultraviolet (UV) light using poly(ethylene glycol) methyl ether methacrylate (PEGMA) as an ion-conducting monomeric unit and tannic acid (TA)-based crosslinking agent and plasticizer. The crosslinking agent and plasticizer based on natural resources are obtained from the reaction of TA with glycidyl methacrylate and glycidyl poly(ethylene glycol), respectively. Dimensionally stable free-standing SPE having a large ionic conductivity of 5.6×10(-4) Scm(-1) at room temperature can be obtained by the polymerization of PEGMA into P(PEGMA) with a very small amount (0.1 wt %) of the crosslinking agent and 2.0 wt % of the plasticizer. The ionic conductivity value of SPE with a crosslinked structure is one order of magnitude larger than that of linear P(PEGMA) in the waxy state.

An antimicrobial peptide, ∼5 kDa in size, was isolated and purified in its active form from the mantle of the Pacific oyster Crassostrea gigas by C18 reversed-phase high-performance liquid chromatography. Matrix-assisted laser desorption ionisation time-of-flight analysis revealed 4656.4 Da of the purified and unreduced peptide. A comparison of the N-terminal amino acid sequence of oyster antimicrobial peptide with deduced amino acid sequences in our local expressed sequence tag (EST) database of C. gigas (unpublished data) revealed that the oyster antimicrobial peptide sequence entirely matched the deduced amino acid sequence of an EST clone (HM-8_A04), which was highly homologous with the β-thymosin of other species. The cDNA possessed a 126-bp open reading frame that encoded a protein of 41 amino acids. To confirm the antimicrobial activity of C. gigas β-thymosin, we overexpressed a recombinant β-thymosin (rcgTβ) using a pET22 expression plasmid in an Escherichia coli system. The antimicrobial activity of rcgTβ was evaluated and demonstrated using a bacterial growth inhibition test in both liquid and solid cultures.

A Gram-stain-negative, aerobic, non-motile, rod-shaped bacterial strain, designated YSS-7T, was isolated from a sea squirt (Halocynthia roretzi) collected from the South Sea of South Korea. Strain YSS-7T grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 2.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain YSS-7T clustered with the type strains of Pelagicola litoralis , Planktotalea frisia , Pacificibacter maritimus and Roseovarius marinus . Strain YSS-7T exhibited the highest 16S rRNA gene sequence similarity (97.7 %) to the type strain of Pelagicola litoralis and sequence similarity of more than 96.0 % to the type strains of some other species. Strain YSS-7T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and 11-methyl C18 : 1ω7c as the major fatty acids. The major polar lipids of strain YSS-7T were phosphatidylcholine, phosphatidylglycerol, an unidentified aminolipid and an unidentified lipid. The fatty acid and polar lipid profiles of strain YSS-7T were different from those of the type strains of phylogenetically related species. The DNA G+C content of strain YSS-7T was 55.5 mol%. Other phenotypic properties demonstrated that strain YSS-7T is distinguished from phylogenetically related species. On the basis of the data presented, strain YSS-7T is considered to represent a novel genus and species, for which the name Pseudopelagicola gijangensis gen. nov., sp. nov. is proposed. The type strain of Pseudopelagicola gijangensis is YSS-7T ( = KCTC 42049T = CECT 8540T).

A series of nitrogen- and sulfone-containing polymers with different molecular weights and monomer compositions were prepared via free radical polymerization to investigate the effect of polymer structure on the ArF lithographic performance in negative tone development (NTD) process. Conventional ArF photoresist polymers (Ref) were also prepared for comparison purposes. It was found that there are optimum molecular weights of the photoresist polymers to give good lithographic performance in NTD process. Photoresists with amine-containing polymers showed contact hole (CH) patterns with some defects, which could be due to the large amount of acid-quenchable amine moieties in the polymers. Lithographic performance of photoresists with sulfonate-containing polymers was close to that with Ref polymers and much better than that with sulfonamide-containing polymers.

A Gram-negative, strictly aerobic, non-flagellated and rod-shaped bacterial strain, designated MA-E2-3(T), was isolated from an ascidian (Halocynthia roretzi) collected from the South Sea, South Korea. Strain MA-E2-3(T) was found to grow optimally at 30 °C, at pH 7.0-8.0 and in the presence of 2.0-3.0 % (w/v) NaCl. A neighbour-joining phylogenetic tree based on 16S rRNA gene sequences revealed that strain MA-E2-3(T) fell within the clade comprising Ruegeria species, clustering consistently with the type strain of Ruegeria halocynthiae, with which it exhibited 98.2 % sequence similarity. Sequence similarities to the type strains of the other recognized Ruegeria species were 94.7-97.7 %. Strain MA-E2-3(T) was found to contain Q-10 as the predominant ubiquinone and C18:1 ω7c as the predominant fatty acid. The major polar lipids of strain MA-E2-3(T) were identified as phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain MA-E2-3(T) was determined to be 58.0 mol%. Mean DNA-DNA relatedness values between strain MA-E2-3(T) and the type strains of four phylogenetically closely related Ruegeria species were in the range of 13-23 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain MA-E2-3(T) is separated from other Ruegeria species. On the basis of the data presented, strain MA-E2-3(T) (=KCTC 32450(T) = CECT 8411(T)) represents a novel species of the genus Ruegeria, for which the name Ruegeria meonggei sp. nov. is proposed.