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Phasin (PhaP), one of the polyhydroxyalkanoate granule-associated protein, enhances cell growth and polyhydroxybutyrate (PHB) biosynthesis by regulating the number and size of PHB granules. However, few studies have applied phasins to various PHB production conditions. In this study, we identified novel phasin genes from the genomic data of Arctic soil bacterium Pseudomonas sp. B14-6 and determined the role of phaP1Ps under different PHB production conditions. Transmission electron microscopy and gel permeation chromatography revealed small PHB granules with high-molecular weight, while differential scanning calorimetry showed that the extracted PHB films had similar thermal properties. The phasin protein derived from Pseudomonas sp. B14-6 revealed higher PHB production and exhibited higher tolerance to several lignocellulosic biosugar-based inhibitors than the phasin protein of Ralstonia eutropha H16 in a recombinant Escherichia coli strain. The increased tolerance to propionate, temperature, and other inhibitors was attributed to the introduction of phaP1Ps, which increased PHB production from lignocellulosic hydrolysate (2.39-fold) in the phaP1Ps strain. However, a combination of phasin proteins isolated from two different sources did not increase PHB production. These findings suggest that phasin could serve as a powerful means to increase robustness and PHB production in heterologous strains.

Community-associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) is notorious as a leading cause of soft tissue infections. Despite several studies on the Agr regulator, the mechanisms of action of Agr on the virulence factors in different strains are still unknown. To reveal the role of Agr in different CA-MRSA, we investigated the LACΔagr mutant and the MW2Δagr mutant by comparing LAC (USA300), MW2 (USA400), and Δagr mutants. The changes of Δagr mutants in sensitivity to oxacillin and several virulence factors such as biofilm formation, pigmentation, motility, and membrane properties were monitored. LACΔagr and MW2Δagr mutants showed different oxacillin sensitivity and biofilm formation compared to the LAC and MW2 strains. Regardless of the strain, the motility was reduced in Δagr mutants. And there was an increase in the long chain fatty acid in phospholipid fatty acid composition of Δagr mutants. Other properties such as biofilm formation, pigmentation, motility, and membrane properties were different in both Δagr mutants. The Agr regulator may have a common role like the control of motility and strain-dependent roles such as antibiotic resistance, biofilm formation, change of membrane, and pigment production. It does not seem easy to control all MRSA by targeting the Agr regulator only as it showed strain-dependent behaviors.

Among various species of marine bacteria, those belonging to the genus Halomonas have several promising applications and have been studied well. However, not much information has been available on their antibiotic resistance. In our efforts to learn about the antibiotic resistance of strain Halomonas socia CKY01, which showed production of various hydrolases and growth promotion by osmolytes in previous study, we found that it exhibited resistance to multiple antibiotics including kanamycin, ampicillin, oxacillin, carbenicillin, gentamicin, apramycin, tetracycline, and spectinomycin. However, the H. socia CKY01 resistance pattern to kanamycin, gentamicin, apramycin, tetracycline, and spectinomycin differed in the presence of 10% NaCl and 1% NaCl in the culture medium. To determine the mechanism underlying this NaCl concentration-dependent antibiotic resistance, we compared four aminoglycoside resistance genes under different salt conditions while also performing time-dependent reverse transcription PCR. We found that the aph2 gene encoding aminoglycoside phosphotransferase showed increased expression under the 10% rather than 1% NaCl conditions. When these genes were overexpressed in an Escherichia coli strain, pETDuet-1::aph2 showed a smaller inhibition zone in the presence of kanamycin, gentamicin, and apramycin than the respective control, suggesting aph2 was involved in aminoglycoside resistance. Our results demonstrated a more direct link between NaCl and aminoglycoside resistance exhibited by the H. socia CKY01 strain.

Cadaverine, 1,5-diaminopentane, is one of the most promising chemicals for biobased-polyamide production and it has been successfully produced up to molar concentration. Pyridoxal 5′-phosphate (PLP) is a critical cofactor for inducible lysine decarboxylase (CadA) and is required up to micromolar concentration level. Previously the regeneration of PLP in cadaverine bioconversion has been studied and salvage pathway pyridoxal kinase (PdxY) was successfully introduced; however, this system also required a continuous supply of adenosine 5′-triphosphate (ATP) for PLP regeneration from pyridoxal (PL) which add in cost. Herein, to improve the process further a method of ATP regeneration was established by applying baker’s yeast with jhAY strain harboring CadA and PdxY, and demonstrated that providing a moderate amount of adenosine 5′-triphosphate (ATP) with the simple addition of baker’s yeast could increase cadaverine production dramatically. After optimization of reaction conditions, such as PL, adenosine 5′-diphosphate, MgCl2, and phosphate buffer, we able to achieve high production (1740 mM, 87% yield) from 2 M l-lysine. Moreover, this approach could give averaged 80.4% of cadaverine yield after three times reactions with baker’s yeast and jhAY strain. It is expected that baker’s yeast could be applied to other reactions requiring an ATP regeneration system.

Poly(3-hydroxybutyrate) (PHB) is a common polyhydroxyalkanoate (PHA) with potential as an alternative for petroleum-based plastics. Previously, we reported a new strain, Halomonas sp. YLGW01, which hyperproduces PHB with 94% yield using fructose. In this study, we examined the PHB production machinery of Halomonas sp. YLGW01 in more detail by deep-genome sequencing, which revealed a 3,453,067-bp genome with 65.1% guanine-cytosine content and 3054 genes. We found two acetyl-CoA acetyltransferases (Acetoacetyl-CoA thiolase, PhaA), one acetoacetyl-CoA reductase (PhaB), two PHB synthases (PhaC1, PhaC2), PHB depolymerase (PhaZ), and Enoyl-CoA hydratase (PhaJ) in the genome, along with two fructose kinases and fructose transporter systems, including the phosphotransferase system (PTS) and ATP-binding transport genes. We then examined the PHB production by Halomonas sp. YLGW01 using high-fructose corn syrup (HFCS) containing fructose, glucose, and sucrose in sea water medium, resulting in 7.95 ± 0.11 g/L PHB (content, 67.39 ± 0.34%). PHB was recovered from Halomonas sp. YLGW01 using different detergents; the use of Tween 20 and SDS yielded micro-sized granules with high purity. Overall, these results reveal the distribution of PHB synthetic genes and the sugar utilization system in Halomonas sp. YLGW01 and suggest a possible method for PHB recovery.

Psychrophilic bacteria, living at low and mild temperatures, can contribute significantly to our understanding of microbial responses to temperature, markedly occurring in the bacterial membrane. Here, a newly isolated strain, Pseudomonas sp. B14-6, was found to dynamically change its unsaturated fatty acid and cyclic fatty acid content depending on temperature which was revealed by phospholipid fatty acid (PLFA) analysis. Genome sequencing yielded the sequences of the genes Δ-9-fatty acid desaturase (desA) and cyclopropane-fatty acid-acyl-phospholipid synthase (cfa). Overexpression of desA in Escherichia coli led to an increase in the levels of unsaturated fatty acids, resulting in decreased membrane hydrophobicity and increased fluidity. Cfa proteins from different species were all found to promote bacterial growth, despite their sequence diversity. In conclusion, PLFA analysis and genome sequencing unraveled the temperature-related behavior of Pseudomonas sp. B14-6 and the functions of two membrane-related enzymes. Our results shed new light on temperature-dependent microbial behaviors and might allow to predict the consequences of global warming on microbial communities.

Older adults experience increased risk for morbidity and mortality during the COVID-19 pandemic (CDC, 2021). Social distancing and lockdown to prevent contagion may affected physical and mental health. We examined the fifteen physical symptom trajectories of older adults during the early months of the COVID-19 pandemic. We also examined age, gender, and marital status differences in each physical symptom trajectory. The sample consisted of 247 older adults (Mage = 71.1, SD = 7.3, 88.7% White, 73% women, 73.4% married), who participated in eight weekly longitudinal online surveys from April 28 to June 23, 2020. Random-effects logistic regression analysis controlling for age, gender, marital status, and depressive symptoms showed that the nine physical symptoms (headache, constipation/diarrhea, muscle soreness, shortness of breath, tightness of chest, backache, heart pounding, congestion, and sore throat) significantly decreased in the first few weeks, but then six symptoms (constipation/diarrhea, shortness of breath, tightness of chest, heart pounding, congestion, and sore throat) increased in later weeks of the study period. Middle-aged participants reported higher number of headache, tightness of chest, heart pounding, and nausea/upset stomach than older participants. Women experienced more constipation/diarrhea, trembling/shaking, and sore throat than men. Those who were not married responded with higher number of shortness of breath, backache and poor appetite compared to married participants. Higher depressive symptoms were significantly related to each physical symptom. The results suggest that healthcare providers should evaluate physical symptoms focusing on the patients who are at greater risk of poor health during the pandemic.

Despite their greater physiological vulnerability, community-residing older adults have shown surprising psychological resilience, at least at the beginning of the COVID-19 pandemic. However, a handful of reports suggest that older adults’ well-being has decreased after a few months, although others have suggested a recovery after a year (Schlomann et al., 2021). The purpose of this study was to examine change in change from baseline (April-May, 2020) to a 13- month follow-up (June, 2021). We analyzed data from 162 older adults with complete data at both time points. Mean age at baseline was 72, SD = 7.6, range = 51-96; 71% were female, 13% were minorities; 74% were married, 71% retired, and most (85%) had at least a BA. Linear modelling showed that there were only marginal increases in the number of problems across time (B = .25, p = .08), but their severity did not increase. There were no significant changes in depression, anxiety, loneliness or physical symptoms over this time period. The modest increase in problems may have been offset by an end to being in lockdown and an increase in social contacts which doubled over this time period, B = 1.65, p

Despite higher physiological vulnerability to stress, older adults may accumulate resources through prior experiences that can promote resilience (Aldwin & Igarashi, 2016). During the COVID-19 pandemic, older adults drew on prior experiences and resources to cope (McKinlay et al., 2021; Herron et al., 2021), although these events were typically not specified. Some found vulnerability due to prior trauma (Galica et al., 2021). We examined whether older adults drew upon specific experiences or more general resilience resources in coping with this novel stressor. Data were collected using an online survey from April 28-May 4, 2020 from 235 older adults in Oregon (Mage = 71.35, SD = 7.39; 74% female; 92% White). We examined open-ended responses from a question that asked whether prior experiences influenced how they were dealing with the COVID-19 situation. Nearly 2/3 provided valid responses (n=144). After inductive open coding, preliminary consolidation resulted in three broad categories: past experiences (74%), resources (19%), and both (8%). The most common prior experiences were illness (n = 20) and work (n = 19). Some (n=10) reported specific coping strategies learned during prior stressful experiences. Resources include personal characteristics (e.g., being “introverted” or “resilient”), financial (“financially secure”) and social resources (“loving spouse”). Five reported experiences that made COVID-19 more difficult (“PTSD/anxiety prior to COVID-19 makes this even worse”). Although 1/3 of the sample could not draw upon a prior experience in coping with this novel stressor, many older participants could utilize their lived experience when coping with problems during the COVID-19 pandemic.

Bacteria can evade antibiotics by acquiring resistance genes, as well as switching to a non-growing dormant state without accompanying genetic modification. Bacteria in this quiescent state are called persisters, and this non-inheritable ability to withstand multiple antibiotics is referred to as antibiotic tolerance. Although all bacteria are considered to be able to form antibiotic-tolerant persisters, the antibiotic tolerance of extremophilic bacteria is poorly understood. Previously, we identified the psychrotolerant bacterium

γ-Aminobutyric acid (GABA), an important fine chemical in pharmacotherapy and food industries, is used as a novel material in the nylon industry and has attracted attention for its potential application in large scale production. Search for new genes and strains, development of efficient reaction systems, such as fermentation and bioconversion, and use of cheap starting material like monosodium glutamate (MSG) can make GABA production using less expensive bulk chemicals possible. Therefore, in this study, we constructed a recombinant Escherichia coli whole-cell system for GABA production that expressed glutamate decarboxylase (GAD) from Lactobacillus brevis and used MSG as the starting material. We also optimized the reaction conditions for MSG to GABA conversion, such as citrate buffer concentration, pyridoxal 5′te concentration, temperature, MSG concentration, and cell density (OD600). The optimized whole-cell system converted MSG to GABA via seven repetitive cycles resulting in an average conversion rate of 86% (71.7 mM/h) within 42 h.

Social support is important for optimal aging, especially during the COVID-19 pandemic when older adults are at risk of social isolation and its attendant health problems. Providing support may be especially protective of health outcomes. We examined whether actual received, provided, and satisfaction with support were related to optimal aging early in the pandemic (April-May, 2020). Survey participants (N=238) were on average 71.2 years old (SD=7.3), 73% female, 92.6% White, and highly educated (48% with post-graduate degrees). Optimal aging (Aldwin & Igarashi, 2016) was indicated by a latent variable of health outcomes, including depressive symptoms, cognitive lapses, and physical symptoms. Nearly all older adults (90+%) reported receiving or providing actual support from or to at least one family member or friend. We investigated the associations between age, summed social support, satisfaction with support, and health outcomes, controlling for chronic illnesses. Two SEM models were estimated for received support and provided support, respectively. After trimming non-significant paths, both models had acceptable fits (CFI > .90, RMSEA < .08, SRMR < .08). Age and chronic illnesses had negative associations with health outcomes, but neither received nor provided social support was significant. However, satisfaction with both received and provided support were significant and independently associated with optimal aging in both models. Thus, isolation levels in this sample were surprisingly low, as indicated by high levels of social support received and provided. However, only the quality of (or satisfaction with) support was important for optimal aging during this unique and shared stressful experience.

Older adults face particular challenges during the COVID-19 pandemic, including increased risk for morbidity and mortality (CDC, 2021). Social distancing and lockdown to prevent contagion may create social isolation and loneliness, adversely affecting mental and physical health. We examined anxiety symptom trajectories of older adults and identified risk and protective factors during the early months of the COVID-19 pandemic. We also examined how anxiety symptoms were associated with both between- and within-person variations in loneliness, social contacts, and physical problems. We sampled 247 older adults (Mage = 71.1, SD = 7.3, range = 51 - 95), who participated in eight weekly longitudinal online surveys from April 28 to June 23, 2020. Multilevel modeling analysis controlling for age, gender, marital status, and education showed that anxiety symptoms significantly decreased in the first few weeks, but then increased around week 6 of the study period. At the between-person level, individuals with higher levels of both loneliness and physical problems were at risk for experiencing higher levels of anxiety, but social contacts were not significant. Middle-aged participants reported higher anxiety symptoms than older participants. Women experienced higher anxiety symptoms than men. As a protective factor, individuals who were high in resilience had significantly lower anxiety symptoms over time, compared to those with low in resilience. In the within-person level, anxiety symptoms were positively coupled with both loneliness and physical symptoms over time. We conclude that lonely individuals and those in poor health were at greater risk of poor mental health during the pandemic.

To assess the clinical characteristics of the rare Kluyvera ascorbata infection, we reviewed the medical records of patients from whom K. ascorbata was isolated from 2010 to 2016, and conducted a systematic review of the English and Spanish literature in PubMed for reports of K. ascorbata infection in humans from 1971 to 2018. A total of 43 cases (24 adults and 19 children) were enrolled: 3 at our hospital and 40 from the literature review. The urinary tract was the most common site of infection (44.2%, 19/43), followed by the bloodstream (27.9%, 12/43). There was no significant difference in the frequency of urinary tract infections (50% vs 36.8%; P = 0.388) and bloodstream infections (25% vs 31.6%; P = 0.633) in adults and children. Seventeen (60.7%, present in 28 of 43 cases) had nosocomial or healthcare-associated infections: 72.7% among children and 60% among adults. Superinfection developed in 20% (6 in 30 cases). The overall mortality was 12.1%. The antimicrobial agents mainly used in these 43 cases were third-generation cephalosporin, cefepime, piperacillin-tazobactam, ciprofloxacin, amikacin, and carbapenem. Most strains were resistant to ampicillin and first- and second-generation cephalosporins. K. ascorbata is a rare but significant clinical pathogen in adults and children.

Several cross-sectional studies have examined stressors and positive events among older adults during COVID-19. We extend these studies by examining changes across time in perceptions of stress and positive experiences. Older adults in Oregon (Mage = 71.1, SD = 7.3, range = 51-95) completed weekly surveys from April 28 to June 23, responding to an adaptation of the Daily Stress Inventory (DISE; Almeida et al., 2002). DISE examines stressors and positive experiences across six domains (health, spouse/partner, other relationships, work/volunteer, finances, and retirement) on a 7-point scale (1 = not at all to 7 = extremely). At baseline, those who felt more stressed were younger, female, and reported more chronic health conditions, while younger adults, especially males, reported more positive events. Positive and stress intensity scores were not correlated. Multilevel models found that for both positive, Blinear = -2.54, SE = 0.52, p < .001; Bquadratic = 0.21, p < .05, and stress, Blinear = -0.79, p < .001; Bquadratic = 0.07, p

Community-associated Methicillin-Resistant

Objectives We examined sources of vulnerability and resilience among older adults early in the coronavirus disease 2019 (COVID-19) pandemic. Methods We surveyed 235 respondents, 51–95 years old (M = 71.35; SD = 7.39; 74% female), including 2 open-ended questions concerning COVID-19-related difficulties and positive experiences during the past week. Using inductive coding, we found 9 final codes for difficulties and 12 for positives and grouped them into socioecological levels: personal, interpersonal, and societal. Results Difficulties were reported by 94% of the sample, while 63% described positives. Difficulties and positive responses were made at all socioecological levels and illustrated a dialectic between personal-level constraints and opportunities, interpersonal-level social isolation and integration, and societal-level outrage, sorrow, and social optimism. Discussion Respondents described sources of vulnerabilities and resilience that supported a socioecological approach to understand resilience during this pandemic. A notable example was resilience derived from witnessing and contributing to the community and social solidarity, highlighting the potential of older adults as resources to their communities during the global pandemic.

Polyhydroxyalkanoates (PHAs) are attractive new bioplastics for the replacement of plastics derived from fossil fuels. With their biodegradable properties, they have also recently been applied to the medical field. As poly(3-hydroxybutyrate) produced by wild-type Ralstonia eutropha has limitations with regard to its physical properties, it is advantageous to synthesize co- or terpolymers with medium-chain-length monomers. In this study, tung oil, which has antioxidant activity due to its 80% α-eleostearic acid content, was used as a carbon source and terpolymer P(53 mol% 3-hydroxybytyrate-co-2 mol% 3-hydroxyvalerate-co-45 mol% 3-hydroxyhexanoate) with a high proportion of 3-hydroxyhexanoate was produced in R. eutropha Re2133/pCB81. To avail the benefits of α-eleostearic acid in the tung oil-based medium, we performed partial harvesting of PHA by using a mild water wash to recover PHA and residual tung oil on the PHA film. This resulted in a film coated with residual tung oil, showing antioxidant activity. Here, we report the first application of tung oil as a substrate for PHA production, introducing a high proportion of hydroxyhexanoate monomer into the terpolymer. Additionally, the residual tung oil was used as an antioxidant coating, resulting in the production of bioactive PHA, expanding the applicability to the medical field.

The present investigation deals with the adsorptive removal of crude petroleum oil from the water surface using coconut oil-modified pinewood biochar. Biochar generated at higher pyrolysis temperature (700 °C) revealed higher fatty acid-binding efficiency responsible for the excellent hydrophobicity of the biochar. Fatty acids composition attached to the biochar produced at 700 °C was (mg g−1 BC) lauric acid (9.024), myristic acid (5.065), palmitic acid (2.769), capric acid (1.639), oleic acid (1.362), stearic acid (1.114), and linoleic acid (0.130). Simulation of the experimental adsorption data of pristine and modified pinewood biochar generated at 700 °C offered the best fit to pseudo-first-order kinetics (R2 > 0.97) and Langmuir isotherm model (R2 > 0.99) based on the highest regression coefficients. Consequently, the adsorption process was mainly driven by surface hydrophobic interactions including π-π electron-donor-acceptor between electron-rich (π-donor) polycyclic aromatic hydrocarbons from the crude oil and biochar (π-acceptor). A maximum adsorption capacity (Qmax) of 5.315 g g−1 was achieved by modified floating biochar within 60 min. Whereas the reusability testing revealed 49.39% and 51.40% was the adsorption efficiency of pristine and modified biochar at the fifth adsorption-desorption cycle.

In the present study, an exopolysaccharide (EPS)-producing bacterial strain was isolated from the Eastern Sea (Sokcho Beach) of South Korea and identified as Sphingobium yanoikuyae BBL01. Media optimization was performed using response surface design, and a yield of 2.63 ± 0.02 g/L EPS was achieved. Purified EPS produced using lactose as the main carbon source was analyzed by GC–MS and found to be composed of α-D-xylopyranose (28.6 ± 2.0%), β-D-glucopyranose (21.0 ± 1.6%), α-D-mannopyranose (18.5 ± 1.2%), β- d -mannopyranose (13.1 ± 1.4%), β-D-xylopyranose (10.2 ± 2.1%), α- d -talopyranose (5.9 ± 1.1%), and β- d -galacturonic acid (2.43 ± 0.8%). Interestingly, different carbon sources (glucose, galactose, glycerol, lactose, sucrose, and xylose) showed no effect on EPS monomer composition, with a slight change in the mass percentage of various monosaccharides. Purified EPS was stable up to 233 °C, indicating its possible suitability as a thickening and gelling agent for food-related applications. EPS also showed considerable emulsifying, flocculating, free-radical scavenging, and metal-complexion activity, suggesting various biotechnological applications.

Among various species of marine bacteria, those belonging to the genus

The present study aimed towards adsorptive removal of the toxic azo dye onto biochar derived from Eucheuma spinosum biomass. Characterization of the produced biochar was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and Brunauer-Emmett-Teller (BET). Eucheuma spinosum biochar (ES-BC) produced at 600 °C revealed a maximum adsorption capacity of 331.97 mg/g towards reactive red 120 dye. The adsorption data fitted best to the pseudo-second order kinetics (R2 > 0.99) and Langmuir isotherm (R2 > 0.98) models. These adsorption models signified the chemisorption mechanism with monolayer coverage of the adsorbent surface with dye molecules. Furthermore, the adsorption process was mainly governed by electrostatic interaction, ion exchange, metal complexation, and hydrogen bonding as supported by the solution pH, FTIR, XPS, and XRD investigation. Nevertheless, alone adsorption technology could not offer a complete solution for eliminating the noxious dyes. Therefore, the bioelectrochemical system (BES) equipped with previously isolated marine Shewanella marisflavi BBL25 was intended for the complete remediation of azo dye. The BES II demonstrated highest dye decolorization (97.06%) within 48 h at biocathode where the reductive cleavage of the azo bond occurred. Cyclic voltammetry (CV) studies of the BES revealed perfect redox reactions taking place where the redox mediators shuttled the electrons to the dye molecule to accelerate the dye decolorization. Besides, the GC-MS analysis revealed biotransformation of the dye into less toxic metabolites as tested using a phyto and cytogenotoxicity.

Phenol-soluble modulins (PSMs) are responsible for regulating biofilm formation, persister cell formation

Pipecolic acid, a non-proteinogenic amino acid, is a metabolite in lysine metabolism and a key chiral precursor in local anesthesia and macrolide antibiotics. To replace the environmentally unfriendly chemical production or preparation procedure of pipecolic acid, many biological synthetic routes have been studied for a long time. Among them, synthesis by lysine cyclodeaminase (LCD), encoded by pipA, has several advantages, including stability of enzyme activity and NAD+ self-regeneration. Thus, we selected this enzyme for pipecolic acid biosynthesis in a whole-cell bioconversion. To construct a robust pipecolic acid production system, we investigated important conditions including expression vector, strain, culture conditions, and other reaction parameters. The most important factor was the introduction of multiple pipA genes into the whole-cell system. As a result, we produced 724 mM pipecolic acid (72.4 % conversion), and the productivity was 0.78 g/L/h from 1 M l-lysine after 5 days. This is the highest production reported to date.

MRSA is Methicillin-resistantStaphylococcus aureusand they are widespread and making trouble in treatment in communities and surgical areas. MRSA have been adapted to antibiotics so that they can block the access of antibiotics physically or chemically deactivate it or modify the precursor of the target. Flavonoids are secondary metabolites which are naturally produced by plant or fungus and they are acting generally as pigment, quorum sensing molecules, antibiotics to other competitive microorganisms. Their natural origins and multiple activities have drawn much attention to be developed as the potential drugs since flavonoids could be a good candidate to overcome antibiotic resistant bacteria. Among various flavonoids, we found out naringenin has antibacterial activity on MRSA and Δagrmutants which are more resistance than MRSA to beta-lactam antibiotics by decreasing biofilm formation dramatically and decreasing the secretion of fatty acid. It also showed high synergetic activity with oxacillin to both antibacterial activity and biofilm inhibition. Considering the number of flavonoids, our experiments expand the possibility of the use of flavonoids to MRSA.

Polyhydroxyalkanoates (PHA), such as poly (3-hydroxybutyrate) (PHB), have emerged as potential alternatives to petroleum-based plastics and can be produced through the appropriate selection of marine bacteria that are already adapted to high salt and low temperature conditions without the requirement of antibiotic treatment. The present study, thus, aimed to screen and characterize thirteen PHA-producing microbial strains isolated from the Gwangalli beach in Busan, South Korea. Among them, Halomonas sp. YLGW01 produced the highest amount of PHB (94.6 ± 1.8% (w/w)) using fructose. Interestingly Halomonas sp. YLGW01 showed increase in cell size (8.39 ± 3.63 μm) with fructose as carbon source as compared to glucose (2.34 ± 0.44 μm). Fructose syrup was investigated as carbon source under unsterilized conditions and 95.26 ± 1.78% of PHB was produced. Overall, this strain showed the highest PHB contents in halotolerant bacteria.

국내 업사이클링(Upcycling) 시장이 가파르게 성장하고 있다. 이에 본 연구는 지역 문화를 기반으로 하는 업사이클링 디자인에 주목하여 한국의 간판 제작에 주로 사용되는 아크릴(Acrylic)을 활용한 업사이클링 장신구 디자인 연구를 목적으로 하였다. 문헌연구 방법과 사례연구 방법으로 진행하였다. 먼저 문헌연구를 통해 재활용 패러다임(Paradigm)의 변화와 아크릴의 특성, 한국 간판 동향의 이론적 고찰을 진행하였다. 다음으로 업사이클링을 통한 장신구 디자인의 국내외 사례 9개 중 11개의 업사이클링 장신구디자인을 선정하여 업사이클링 디자인 제작 기법(이루미 등, 2015)으로 분석하였다. 사례 분석 결과 5가지의 업사이클링 디자인 기법 중 Melting and Compressing 기법은 업사이클링 장신구에 활용되지 않았다. 자투리 아크릴을 활용한 업사이클링 장신구의 경우에도 위의 기법을 제외한 나머지 4가지 기법이 적용 가능하였다. 결론적으로 자투리 아크릴의 무독성, 경량성 등의 특성으로 미루어 볼 때 자투리 아크릴은 장신구 디자인 소재로 활용이 적합하였다. 더불어 유광 아크릴의 표면은 장신구의 반짝임을 표현하였다. 본 연구에서는 다양한 업사이클링 기법을 활용한 자투리 아크릴 장신구 디자인 제안하였다. 향후 연구에서는 업사이클링 장신구 디자인의 조형적 연구와 더불어 자투리 아크릴을 활용한 다양한 업사이클링 연구을 기대한다.

BACKGROUND The molecular characterization of Streptococcus dysgalactiae subsp. equisimilis (SDSE) has not yet been performed in Korea. This study aimed to find the differences or similarities in the clinical features, molecular epidemiological findings, and antimicrobial resistance patterns of SDSE from two countries (Korea and Japan). METHODS SDSE isolates were collected from Korea (N=69) from 2012-2016 and Japan (N=71) from 2014-2016. Clinical characteristics, emm genotypes, and sequence types (STs) were compared. Microdilution tests were performed using different antimicrobials, and their resistance determinants were screened. RESULTS Median ages were 69 years in Korea and 76 years in Japan. The most common underlying diseases were diabetes and malignancy. Blood-derived isolates comprised 36.2% and 50.7% of Korean and Japanese isolates, respectively; mortality was not different between the two groups (5.8% vs 9.9%, P=0.53). Among Korean isolates with 20 different combined ST-emm types, ST127-stG245 (N=16), ST128-stG485 (N=10), and ST138-stG652 (N=8) were prevalent. Among Japanese isolates with 29 different combined types, ST17-stG6792 (N=11), ST29-stG485 (N=7), and ST205-stG6792 (N=6) were prevalent. Resistance rates to erythromycin, clindamycin, and minocycline were 34.8%, 17.4%, and 30.4% in Korea and 28.2%, 14.1%, and 21.4% in Japan, respectively. CONCLUSIONS SDSE infections commonly occurred in elderly persons with underlying diseases. There was a significant difference in the distribution of ST-emm types between the two countries. Antimicrobial resistance rates were comparable with different frequencies of resistance determinants in each country.

While older Koreans have growing access to Internet, they still lag in actual utilization. This study examined effects of different information support sources on Internet utilization and whether these were mediated by Internet skills and technology attitudes among older men and women. This study used secondary data from 2019 Digital Divide Survey conducted by National Information Society Agency of Korea. The sample consisted of 1,031 Korean Internet users aged 60+, including 495 men and 536 women. Support sources included personal and professional. Skills were measured by ability to use specific features of mobile devices such as smartphones (seven items), while utilization was measured by the use of mobile devices for specific reasons (25 items). Serial mediation analyses using both skills and attitudes were conducted separately according to gender and support sources, covarying for demographics and health. In general, information support was positively associated with utilization. For men, personal informational support was mediated by technology attitudes only. For women, professional informational support was mediated by both Internet skills and technology attitudes, but the serial indirect effect was not significant for this model. The other two models showed significant serial mediation effects through Internet skills and technology attitudes, in this order. Only women had significant direct associations between information support and Internet utilization. Regardless of the source, informational support is positively associated with older Koreans’ Internet utilization. Professional support for men and personal support for women may be most beneficial for greater Internet utilization.