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The wide use of whole-genome sequencing approach in the modern genomic era has opened a great opportunity to reveal the prospective applications of halophilic bacteria. Robertkochia marina CC-AMO-30D T is one of the halophilic bacteria that was previously taxonomically identified without any inspection on its biotechnological potential from a genomic aspect. In this study, we present the whole-genome sequence of R. marina and demonstrated the ability of this bacterium in solubilizing phosphate by producing phosphatase. The genome of R. marina has 3.57 Mbp and contains 3107 predicted genes, from which 3044 are protein coding, 52 are non-coding RNAs, and 11 are pseudogenes. Several phosphatases such as alkaline phosphatases and pyrophosphatases were mined from the genome. Further genomic study (phylogenetics, sequence analysis, and functional mechanism) and experimental data suggested that the alkaline phosphatase produced by R. marina could potentially be utilized in promoting plant growth, particularly for plants on saline-based agricultural land.

To date, there is sparse information for the genus Robertkochia with Robertkochia marina CC-AMO-30D T as the only described member. We report here a new species isolated from mangrove soil collected at Malaysia Tanjung Piai National Park and perform polyphasic characterization to determine its taxonomic position. Strain CL23 T is a Gram-negative, yellow-pigmented, strictly aerobic, catalase-positive and oxidase-positive bacterium. The optimal growth conditions were determined to be at pH 7.0, 30-37 °C and in 1-2 % (w/v) NaCl. The major respiratory quinone was menaquinone-6 (MK-6) and the highly abundant polar lipids were four unidentified lipids, a phosphatidylethanolamine and two unidentified aminolipids. The 16S rRNA gene similarity between strain CL23 T and R. marina CC-AMO-30D T is 96.67 %. Strain CL23 T and R. marina CC-AMO-30D T clustered together and were distinguished from taxa of closely related genera in 16S rRNA gene phylogenetic analysis. Genome sequencing revealed that strain CL23 T has a genome size of 4.4 Mbp and a G+C content of 40.72 mol%. Overall genome related indexes including digital DNA-DNA hybridization value and average nucleotide identity are 17.70 % and approximately 70%, below the cutoffs of 70 and 95%, respectively, indicated that strain CL23 T is a distinct species from R. marina CC-AMO-30D T . Collectively, based on the phenotypic, chemotaxonomic, phylogenetic and genomic evidences presented here, strain CL23 T is proposed to represent a new species with the name Robertkochia solimangrovi sp. nov. (KCTC 72252 T =LMG 31418 T ). An emended description of the genus Robertkochia is also proposed.

Strain Corallo1 T was isolated from mucus of red coral (Corallium rubrum) at Punta Pizzaco (Procida island, Naples, Italy). It was characterised as a Gram-stain negative, motile, rod-shaped bacterium. Strain Corallo1 T was found to show positive responses for cytochrome-c oxidase, catalase, reduction of nitrate and nitrite, β-galactosidase activity and hydrolysis of starch, xylan, peptone, Tween 40, Tween 80 and casein. Strain Corallo1 T was found to be mesophilic, neutrophilic to alkalophilic and slightly halophilic. According to analysis of the almost-complete 16S rRNA gene, strain Corallo1 T is closely related to Vibrio celticus (100% sequence similarity), Vibrio gigantis (100%), Vibrio crassostreae (99.7%), Vibrio artabrorum (99.7%) and Vibrio pomeroyi (99.6%). MLSA of five housekeeping genes (atpA, pyrH, recA, rpoA and rpoD) was performed to refine the phylogenetic relationships of strain Corallo1 T . A draft genome sequence of strain Corallo1 T was obtained. The DNA G+C content of this strain was determined to be 44.5 mol %. The major cellular fatty acids of strain Corallo1 T are C 16:1 , n-C 16:0 and C 18:1 , and the major isoprenoid ubiquinone is Q8. ANI indexes, in silico estimations of DDH values and wet lab DDH values demonstrated that strain Corallo1 T represents an independent genomospecies. Based on a polyphasic taxonomic characterisation, strain Corallo1 T is concluded to represent a novel species of the genus Vibrio, for which the name Vibrio coralliirubri sp. nov. is proposed. The type strain is Corallo1 T (= DSM 27495 T  = CIP 110630 T ).

To date, the genus Roseivirga consists of six species with one subspecies and is one of the least-studied genera among the family Flammeovirgaceae. In order to further explore this genus, the genome sequences of five Roseivirga spp. were compared and described in this study. The Roseivirga genomes have similar sizes in the range of 4.08-4.47Mb with an average of 4.22Mb. Several key proteins related to osmotic stress adaptation were identified in Roseivirga spp. including betaine transporter, choline dehydrogenase, and glutamate synthases. Significant amount of proteins associated with amino acid transport and metabolism were also present in Roseivirga genome. All five Roseivirga spp. were able to grow in medium contained casamino acids (mixture of amino acids) as sole carbon or nitrogen sources. Taken together, these findings suggested the potential role of Roseivirga in decomposing organic nitrogen matter in marine environment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Protein engineering is a very useful tool for probing structure-function relationships in proteins. Specifically, site-directed mutagenized proteins can provide useful insights into structural, binding and catalytic mechanisms of a protein, particularly when coupled with crystallization. In this chapter, we describe two protocols for performing site-directed mutagenesis of any protein-coding sequence, namely, megaprimer PCR and overlapping extension PCR (OE-PCR). We use as an example how these two SDM methods enhanced the function of a cyclodextrin glucosyltransferase (CGTase) from Bacillus lehensis strain G1.

Maltose-binding protein (MBP) is a periplasmic binding protein found in Gram negative bacteria. MBP is involved in maltose transport and bacterial chemotaxis; it binds to maltose and maltodextrins comprising α(1-4)-glucosidically linked linear glucose polymers and α(1-4)-glucosidically linked cyclodextrins. Upon ligand binding, MBP changes its conformation from an open to a closed form. This molecular recognition-transducing a ligand-binding event into a physical one-renders MBP an ideal candidate for biosensor development. Here, we describe the construction of a Strep-tag II mutant MBP for reagentless fluorescence sensing. malE, which encodes MBP, was amplified. A cysteine residue was introduced by site-directed mutagenesis to ensure a single label attachment at a specific site with a thiol-specific fluorescent probe. An environmentally sensitive fluorophore (IANBD amide) was covalently attached to the introduced thiol group and analysed by fluorescence sensing. The tagged mutant MBP (D95C) was purified (molecular size, ∼42 kDa). The fluorescence measurements of the IANBD-labelled Strep-tag II-D95C in the solution phase showed an appreciable change in fluorescence intensity (dissociation constant, 7.6±1.75 μM). Our mutant MBP retains maltose-binding activity and is suitable for reagentless fluorescence sensing.

Jeotgalibacillus alimentarius JY-13(T) (=KCCM 80002(T) = JCM 10872(T)) is a moderate halophile. In 2001, this was the first strain of the newly proposed Jeotgalibacillus genus. The draft genome of J. alimentarius was found to consist of 32 contigs (N50, 315,125 bp) with a total size of 3,364,745 bp. This genome information will be helpful for studies on pigmentation as well as applications for this bacterium., (Copyright © 2015 Yaakop et al.)

Anoxybacillus thermarum AF/04(T) was isolated from the Euganean hot springs in Abano Terme, Italy. The present work reports a high-quality draft genome sequence of strain AF/04(T). This work also provides useful insights into glycoside hydrolases, glycoside transferases, and sugar transporters that may be involved in cellular carbohydrate metabolism., (Copyright © 2015 Poli et al.)

The cyclodextrin glucanotransferase (CGTase, EC 2.4.1.19) gene from Bacillus sp. G1 was successfully isolated and cloned into Escherichia coli. Analysis of the nucleotide sequence revealed the presence of an open reading frame of 2,109 bp and encoded a 674 amino acid protein. Purified CGTase exhibited a molecular weight of 75 kDa and had optimum activity at pH 6 and 60 degrees C. Heterologous recombinant protein expression in E. coli is commonly problematic causing intracellular localization and formation of inactive inclusion bodies. This paper shows that the majority of CGTase was secreted into the medium due to the signal peptide of Bacillus sp. G1 that also works well in E. coli, leading to easier purification steps. When reacted with starch, CGTase G1 produced 90% beta-cyclodextrin (CD) and 10% gamma-CD. This enzyme also preferred the economical tapioca starch as a substrate, based on kinetics studies. Therefore, CGTase G1 could potentially serve as an industrial enzyme for the production of beta-CD.

Multimodality image registration via pixel migration is a powerful approach. However, it suffers from a serious problem--the global maximum on the sum of squared gradient magnitude (SSG) surface does not correspond to the correct solution of registration. To solve the problem, we partition the search space into feasible and infeasible regions. The genetic algorithm (global optimizer) is used to obtain a good initial estimate of registration parameters and followed by a fast refining with Powell's approach (local optimizer). The experimental results demonstrate that the use of this modified pixel migration algorithm on multisensor image registration is very effective.

Hyponatremia is an important electrolyte abnormality with the potential for significant morbidity and mortality. Common causes include medications and the syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Hyponatremia can be classified according to the volume status of the patient as hypovolemic, hypervolemic, or euvolemic. Hypervolemic hyponatremia may be caused by congestive heart failure, liver cirrhosis, and renal disease. Differentiating between euvolemia and hypovolemia can be clinically difficult, but a useful investigative aid is measurement of plasma osmolality. Hyponatremia with a high plasma osmolality is caused by hyperglycemia, while a normal plasma osmolality indicates pseudohyponatremia or the post-transurethral prostatic resection syndrome. The urinary sodium concentration helps in diagnosing patients with low plasma osmolality. High urinary sodium concentration in the presence of low plasma osmolality can be caused by renal disorders, endocrine deficiencies, reset osmostat syndrome, SIADH, and medications. Low urinary sodium concentration is caused by severe burns, gastrointestinal losses, and acute water overload. Management includes instituting immediate treatment in patients with acute severe hyponatremia because of the risk of cerebral edema and hyponatremic encephalopathy. In patients with chronic hyponatremia, fluid restriction is the mainstay of treatment, with demeclocycline therapy reserved for use in persistent cases. Rapid correction should be avoided to reduce the risk of central pontine myelinolysis. Loop diuretics are useful in managing edematous hyponatremic states and chronic SIADH. In all instances, identifying the cause of hyponatremia remains an integral part of the treatment plan.