Distinct Genetic Variation of Helicobacter pylori cagA, vacA, oipA, and sabA Genes in Thai and Korean Dyspeptic Patients

Boonyanugomol, Wongwarut,Kongkasame, Worrarat,Palittapongarnpim, Prasit,Jung, Myunghwan,Shin, Min-Kyoung,Kang, Hyung-Lyun,Baik, Seung-Chul,Lee, Woo-Kon,Cho, Myung-Je The Korean Society for Microbiology and Biotechnol 2018 한국미생물·생명공학회지 Vol.46 No.3

Differences in host ethnicities and geographical distributions may influence the genetic variation and pathogenesis of Helicobacter pylori strains, particularly with respect to those with a high risk of gastric cancer and in Asian Enigma regions. We simultaneously identified H. pylori virulence-associated genes involved in inflammation and cell damage in Thai and Korean dyspeptic patients. The virulence-associated gene cagA, cagA genotypes (East Asian and Western type cagA), vacA genotypes (s- and m-), oipA, and sabA were detected in Thai and Korean dyspeptic patients by polymerase chain reaction (PCR), real-time PCR, and DNA sequence analysis. Comparisons between the two regions showed that cagA, East Asian type cagA, and vacA s1/m1 in Korean dyspeptic patients occurred at rates of 100%, 86.67%, and 88.89%, respectively (p < 0.05). The oipA- and sabA-positive samples were significantly more predominant in the Korean population (95.56%, 91.11%) than in the Thai population (32%, 34%). DNA sequence analysis revealed differences in the patterns of cytosine-thymine dinucleotide repeats of oipA and sabA among the two populations of dyspeptic patients. Our results indicate that the H. pylori strains detected in the two regions were divergent, and strains colonizing the Korean dyspeptic patients may be more virulent than those in the Thai population. Our data may help explain H. pylori pathogenesis in Asian Enigma areas with a low gastric cancer incidence. However, other factors involving H. pylori infection in these two regions should be further analyzed.

Microbiological Synthesis of L-Tyrosine and 3,4-Dihydroxy-Phenyl-L-Alanine

Yamada, H. The Korean Society for Microbiology and Biotechnol 1974 한국미생물·생명공학회지 Vol.2 No.2

Application of Bacillus subtilis 168 as a Multifunctional Agent for Improvement of the Durability of Cement Mortar

Park, Sung-Jin,Park, Jong-Myong,Kim, Wha-Jung,Ghim, Sa-Youl The Korean Society for Microbiology and Biotechnol 2012 Journal of microbiology and biotechnology Vol.22 No.11

Microbiological calcium carbonate precipitation (MCCP) has been investigated for its ability to improve the durability of cement mortar. However, very few strains have been applied to crack remediation and strengthening of cementitious materials. In this study, we report the biodeposition of Bacillus subtilis 168 and its ability to enhance the durability of cement material. B. subtilis 168 was applied to the surface of cement specimens. The results showed a new layer of deposited organic-inorganic composites on the surface of the cement paste. In addition, the water permeability of the cement paste treated with B. subtilis 168 was lower than that of non-treated specimens. Furthermore, artificial cracks in the cement paste were completely remediated by the biodeposition of B. subtilis 168. The compressive strength of cement mortar treated with B. subtilis 168 increased by about 19.5% when compared with samples completed with only B4 medium. Taken together, these findings suggest that the biodeposition of B. subtilis 168 could be used as a sealing and coating agent to improve the strength and water resistance of concrete. This is the first paper to report the application of Bacillus subtilis 168 for its ability to improve the durability of cement mortar through calcium carbonate precipitation.

Assessment of Bioremediation Potential of Cellulosimicrobium sp. for Treatment of Multiple Heavy Metals

Bhati, Tushar,Gupta, Rahul,Yadav, Nisha,Singh, Ruhi,Fuloria, Antra,Waziri, Aafrin,Chatterjee, Sayan,Purty, Ram Singh The Korean Society for Microbiology and Biotechnol 2019 한국미생물·생명공학회지 Vol.47 No.2

In the present study, we have studied the bioremediating capability of bacterial strain against six heavy metals. The strain was isolated from river Yamuna, New Delhi which is a very rich repository of bioremediating flora and fauna. The strain was found to be Gram positive as indicated by Gram staining. The strain was characterized using 16s rRNA gene sequencing and the BlastN result showed its close resemblance with the Cellulosimicrobium sp. As each treatment has its own toxicity eliciting expression of different factors, we observed varied growth characteristics of the bacterial isolate and its protein content in response to different heavy metals. The assessment of its bioremediation capability showed that the strain Cellulosimicrobium sp. has potential to consume or sequester the six heavy metals in this study in the following order iron > lead > zinc > cooper > nickel > cadmium. Thus, the strain Cellulosimicrobium sp. isolated in the present study can be a good model system to understand the molecular mechanism behind its bioremediating capabilities under multiple stress conditions.

Cloning and Characterization of Zebrafish Microsomal Epoxide Hydrolase Based on Bioinformatics

이은열,김희숙,Lee Eun-Yeol,Kim Hee-Sook The Korean Society for Microbiology and Biotechnol 2006 한국미생물·생명공학회지 Vol.34 No.2

Zebrafish (Danio rerio)의 microsomal epoxide hydrolase(mEH)로 추정되는 유전자를 클로닝하고 그 특성을 연구하였다. D. rerio의 mEH 추정단백질은 포유동물의 mEH 및 세균의 EH들과 아미노산서열 상동성을 보였으므로 결정분자구조(1qo7 및 1ehy)를 template로 하여 homology modelling을 행하였다. 클로된 단백질은 $Asp^{233}$, $Glu^{413}$ 및 $His^{440}$으로 구성된 catalytic triad와 2개의 tyrosine 잔기 및 oxyanion hole이 보존되어 있었다. 생물정보학적인 분석 및 EH 활성시험은 추정단백질이 D. rerio의 mEH라는 것을 보여주었다. Racemic styrene oxide를 기질로 하여 활성시험을 행한 결과, 재조합 D. rerio mEH는 (R)-styrene oxide을 입체선택적으로 가수분해하였으며 45분 반응시간에 99%ee의 광학순도를 가진 (S)-styrene oxide를 33.5% 얻을 수 있었다. A gene encoding for a putative microsomal epoxide hydrolase (mEH) of a zebrafish, Danio rerio, was cloned and characterized. The putative mEH protein of D. rerio exhibited sequence similarity with mammalian mEH and some other bacterial EHs. A structural model for the putative mEH was constructed using homology modeling based on the crystallographic templates, 1 qo7 and 1 ehy. The catalytic triad consisting of $Asp^{233}$, $Glu^{413}$, and $His^{440}$ was identified, and the characteristic features such as two tyrosine residues and oxyanion hole were found to be highly conserved. Based on bioinformatic analysis together with EH activity assay, the putative protein was annotated as mEH of D. rerio. Enantiopure styrene oxide with enantiopurity of 99%ee and yield of 33.5% was obtained from racemic styrene oxide by the enantioselective hydrolysis activity of recombinant mEH of D. rerio for 45 min.

Competitive Growth and Attachment of Listeria monocytogenes and Lactococcus lactis ssp. lactis ATCC 11454

Lee, Shin-Ho,Frank, Joseph-F. The Korean Society for Microbiology and Biotechnol 1992 Journal of microbiology and biotechnology Vol.2 No.2

The effect of a nisin-producing Lactococcus lactis spp. lactis (L. lactis) on the growth and attachment of Listeria monocytogenes Scott A and Brie 1 on stainless steel and their growth in Brain Heart Infusion broth was determined. Viable cells of Listeria decreased rapidly after 9~12 hr of incubation at $21^{\circ}C$ and after 6~9 hr of incubation at $32^{\circ}C$ in the presence of L. lactis. The number of L. monocytogenes Scott A attached to stainless steel in pure culture was $2.5{\times}10^3/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}2.3{\times}10^3/\textrm{cm}^2{\;}at{\;}32^{\circ}C$ after 48 hr of incubation, but was only $10/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}1.1{\times}10/\textrm{cm}^2{\;}at{\;}32^{\circ}C$ in the presence of L. lactis. Results from L. monocytogenes strain Brie 1 were similar to those from strain Scott A. The population of L. monocytogenes Scott A which attached to stainless steel with previously adherent L. lactis was $1.8{\times}10^2/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}8.2{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$, whereas the population attached to sterile stainless steel was $1.2{\times}10^3/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}2.1{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$. For L. monocytogenes Brie 1, the attached population of the control was $1.6{\times}10^4/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}3.2{\times}10^2/\textrm{cm}^2{\;}at{\;}32^{\circ}C$, and on stainless steel with adherent L. lactis, it was $1.1{\times}10/\textrm{cm}^2{\;}at{\;}21^{\circ}C{\;}and{\;}6.9{\times}10/\textrm{cm}^2{\;}at{\;}32^{\circ}C$. Surface adherent L. lactis was less inhibitory to attachment of L. monocytogenes on stainless steel than a liquid culture inoculum. Listeria attached to stainless steel survived dry storage for 20 days both in the presence and absence of adherent lactococci.

Lipase-producing Filamentous Fungi from Non-dairy Creamer Industrial Waste

Triyaswati, Desty,Ilmi, Miftahul The Korean Society for Microbiology and Biotechnol 2020 한국미생물·생명공학회지 Vol.48 No.2

Lipase-producing fungi have been isolated from environments containing lipids. The non-dairy creamer industrial waste has a high amount of lipids so it is a potential source for the isolation of lipase-producing fungi. However, the study of fungi that secrete lipase from this industrial waste has not been reported. The purpose of this study was to obtain lipase-producing filamentous fungi from non-dairy creamer industrial waste. Mineral salt and potato dextrose agar were used as media for the isolation process. The qualitative screening was conducted using phenol red agar medium and the quantitative screening using broth medium containing glucose and olive oil. Isolates producing the highest amounts of lipase were identified with molecular methods. We found that 5 out of 19 isolated filamentous fungi are lipase producers. Further analysis showed that isolate Ms.11 produced the highest amount of lipase compared to others. Based on ITS sequence Ms.11 was identified as Aspergillus aculeatus. The lipase activity in medium containing 1% glucose + 1% olive oil at pH 7.0 and 30℃ after 96 and 120 h of incubation was 5.13 ± 0.30 U/ml and 5.22 ± 0.59 U/ml, respectively. The optimum lipase activity was found at pH 7.0, 30℃ and using methanol or ethanol in the reaction tube. Lipase was more stable at 20-30℃ and maintained 85% of its activity. It was concluded that isolate Ms.11 is a potential source of lipase that catalyzes transesterification reactions. Further studies are required to optimize lipase production to make the strain suitable for industry purposes.

Microbial Strains and Bioactive Exopolysaccharide Producers from Thai Water Kefir

Luang-In, Vijitra,Saengha, Worachot,Yotchaisarn, Manatchanok,Halaslova, Monika,Udomwong, Piyachat,Deeseenthum, Sirirat The Korean Society for Microbiology and Biotechnol 2018 한국미생물·생명공학회지 Vol.46 No.4

The aims of this novel work were to determine the microbial strains and exopolysaccharide (EPS) producers in water kefir from Nakhon Ratchasima Province, Thailand. Thirty-three microbial strains were identified using 16S rRNA gene analysis consisting of 18 bacterial strains, as 9 strains of acetic acid bacteria (AAB), 9 strains of lactic acid bacteria (LAB), and 15 yeast strains. All bacteria were able to produce EPS with a diverse appearance on agar media containing different sugars at a concentration of 8%. Culture supernatants from AAB and LAB showed 31-64% 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity with the highest antioxidant activity of 64% from Acetobacter pasteurianus WS3 and WS6. Crude EPS from A. pasteurianus WS3 displayed the highest ferric reducing antioxidant power at 280 mM $FeSO_4/g$ EPS, greatest anti-tyrosinase activity at 20.35%, and highest EPS production of 1,505 mg EPS/L from 8% sucrose. These microbes offer beneficial health implications and their EPSs can be used as food additives and cosmetic ingredients.

DnaJ of Streptococcus suis Type 2 Contributes to Cell Adhesion and Thermotolerance

Zhang, Xiaoyan,Jiang, Xiaowu,Yang, Ling,Fang, Lihua,Shen, Hongxia,Lu, Xingmeng,Fang, Weihuan The Korean Society for Microbiology and Biotechnol 2015 Journal of microbiology and biotechnology Vol.25 No.6

To examine if the molecular chaperone DnaK operon proteins of Streptococcus suis type 2 (SS2) are involved in adhesion to host cells, the abundance values of these proteins from the surface of two SS2 strains of different adhesion capability were compared. Their roles in growth and adhesion to human laryngeal epithelial cell line HEp-2 cells were investigated on SS2 strain HA9801 and its mutants with DnaK operon genes partially knocked-out (PKO mutant) under heat stress. The major difference was that DnaJ was more abundant in strain HA9801 than in strain JX0811. Pretreatment of the bacteria with hyperimmune sera to DnaJ, but not with those to other proteins, could significantly reduce SS2 adhesion to HEp-2 cells. PKO of dnaJ g ene resulted in decreased SS2 growth at 37℃ and 42℃, and reduced its adhesion to HEp-2 cells. The wild-type strain stressed at 42℃ had increased expression of DnaJ on its surface and elevated adhesion to HEp-2 cells, which was also inhibitable by DnaJ specific antiserum. These results indicate that the DnaJ of S. suis type 2 is important not only for thermotolerance but also for adhesion to host cells. Because DnaJ expression is increased upon temperature upshift with increased exposure on the bacterial surface, the febrile conditions of the cases with systemic infections might help facilitate bacterial adhesion to host cells. DnaJ could be one of the potential candidates as a subunit vaccine because of its good immunogenicity.

Simplex PCR Assay for Detection of bla_TEM and gyrA Genes, Antimicrobial Susceptibility Pattern and Plasmid Profile of Salmonella spp. Isolated from Stool and Raw Meat Samples in Niger State, Nigeria

Musa, Dickson A.,Aremu, Kolawole H.,Ajayi, Abraham,Smith, Stella I. The Korean Society for Microbiology and Biotechnol 2020 한국미생물·생명공학회지 Vol.48 No.2

The global evolution of antibiotic resistance has threatened the efficacy of available treatment options with ravaging impacts observed in developing countries. As a result, investigations into the prevalence of antibiotic resistance and the role of plasmids are crucial. In this study, we investigated the presence and distribution of bla_TEM and gyrA genes, plasmid profiles, and the antimicrobial susceptibility pattern of Salmonella strains isolated from raw meat and stool sources across Niger State, Nigeria. Ninety-eight samples, comprising 72 raw meat and 26 stool samples, were screened for Salmonella spp. The antimicrobial susceptibility of Salmonella isolates to 10 commonly used antimicrobial agents was determined using the KirbyBauer disc diffusion method. Isolates were further analyzed for plasmids, in addition to PCR amplification of beta-lactamase (bla_TEM) and gyrA genes. A total of 31 Salmonella spp. were isolated, with 22 from raw meat (70.97%) and 9 from stool (29.03%). Salmonella spp. with multiple resistance patterns to ceftazidime, cefuroxime, ceftriaxone, erythromycin, ampicillin, cloxacillin, and gentamicin were detected. Ofloxacin and ciprofloxacin were found to be the most effective among the antibiotics tested, with 67.7% and 93.5% susceptible isolates, respectively. Nine (29.03%) isolates harbored plasmids with molecular sizes ranging between 6557 bp and 23137 bp. PCR amplification of gyrA was detected in 1 (3.23%) of the 31 isolates while 28 isolates (90.32%) were positive for bla_TEM. This study shows the incidence of antibiotic resistance in Salmonella isolates and the possible role of plasmids; it also highlights the prevalence of ampicillin resistance in this local population.