• Journal of Microbiology and Biotechnology
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• 제30권2호
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• pp.237-243
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• 2020

A novel psychrotolerant Psychrobacillus strain PB01, isolated from an Antarctic iceberg, was comparatively analyzed with five related strains. The complete genome of strain PB01 consists of a single circular chromosome (4.3 Mb) and a plasmid (19 Kb). As potential low-temperature adaptation strategies, strain PB01 has four genes encoding cold-shock proteins, two genes encoding DEAD-box RNA helicases, and eight genes encoding transporters for glycine betaine, which can serve as a cryoprotectant, on the genome. The pan-genome structure of the six Psychrobacillus strains suggests that strain PB01 might have evolved to adapt to extreme environments by changing its genome content to gain higher capacity for DNA repair, translation, and membrane transport. Notably, strain PB01 possesses a complete TCA cycle consisting of eight enzymes as well as three additional Helicobacter pylori-type enzymes: ferredoxin-dependent 2-oxoglutarate synthase, succinyl-CoA/acetoacetyl-CoA transferase, and malate/quinone oxidoreductase. The co-existence of the genes for TCA cycle enzymes has also been identified in the other five Psychrobacillus strains.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1163-1168
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• 2006

The recombinant plasmid pLEX2FP complements the mutation in Zoogloea ramigera 115MM1, and the complemented mutant produces an exopolysaccharide that shows higher affinity for the calcofluor dye than the exopolysaccharide from Z. ramigera 115SLR, resulting in higher fluorescence intensity under UV light. A compositional and structural analysis of the exopolysaccharide from Z. ramigera 115MM1 showed that the different fluorescent properties were due to a lower content of acetyl groups when compared with Z. ramigera 115SLR exopolysaccharide. These results were in agreement with a sequence analysis of the gene carried in the plasmid pLEX2FP, which appeared to encode an O-acyltransferase highly homologous to the 3-O-acyltransferase of Streptomyces mycarofaciens. The gene encoding the acyltransferase from Z. ramigera 115SLR was expressed as a GST-fusion protein with 70,000 daltons in E. coli.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2004년도 Annual Meeting BioExibition International Symposium
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• pp.323-327
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• 2004

Leuconostoc citreum CBUE isolated from kimchi proved to harbor a small cryptic plasmid, pNS75. The complete nucleotide sequence of pNS75 was 1,821 bp and had a low G+C content of 39.2%. Computer analysis using DNASIS revealed one open reading frame (ORF), having ATG as putatitive start condon and potentially encoding proteins with molecular mass of 38 kDa. The chimeric plasmid pLeuCM was first constructed wih pNS75, pUC19 and chroamphenicol acetyltransferase (CAT) from Staphylococcus sp.. pLeuCM replicated and expressed chroamphenicol acetyltransferase in Leuconostoc citerum CBNF after transformation. To test the availability of shuttle vector as cloning vehicle of foreign gene, $\alpha$-amylase gene of Streptococcus bovis was cloned and all transformants secreated the $\alpha$-amylase successfully. The result indicates that pLeuCM is a potential shuttle vector for Leuconostoc spp. and lactic acid bacteria.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1983-1993
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• 2017

Salmonella enterica subsp. enterica serovar Typhimurium, one of the most common foodborne pathogens, is transmitted mainly through contaminated food derived from infected animals. In this study, S. Typhimurium ST1120, an isolate from pig feces in Korea, was subjected to whole-genome analysis to understand its genomic features associated with virulence. The genome of ST1120 was found to have a circular chromosome of 4,855,001 bp (GC content 52.2%) and a plasmid of 6,863 bp (GC content 46.0%). This chromosome was predicted to have 4,558 open reading frames (ORFs), 17 pseudogenes, 22 rRNA genes, and 86 tRNA genes. Its plasmid was predicted to have three ORFs. Comparative genome analysis revealed that ST1120 was phylogenetically close to S. Typhimurium U288, a critical isolate in piggery farms and food chains in Europe. In silico functional analysis predicted that the ST1120 genome harbored multiple genes associated with virulence and stress resistance, including Salmonella pathogenicity islands (SPIs containing SPI-1 to SPI-5, SPI-13, and SPI-14), C63PI locus, ST104 prophage locus, and various antibiotic resistance genes. In accordance with these analysis results, ST1120 showed competence in invasion and survival abilities when it was added to host cells. It also exhibited robust resistance against antibiotics in comparison with other S. Typhimurium strains. This is the first report of the complete genome sequence of S. Typhimurium isolated from swine in Korea. Comparative genome analysis between ST1120 and other Salmonella strains would provide fruitful information toward understanding Salmonella host specificity and developing control measures against S. Typhimurium infection.

• 한국약용작물학회지
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• 제24권6호
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• pp.464-470
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• 2016

Background: Valeriana fauriei (Valerianaceae) has been used to as a traditional medicine to treat a variety of symptoms, including headache, insomnia, hypertension, and menstrual irregularity. However, the present study investigates the species' antioxidant activity and its inhibition of oxidative DNA damage, which have yet to be studied. Methods and Results: The antioxidant activity was assessed using radical scavenging assays with 1,1-diphenyl-2-picryl hydrazyl (DPPH) and, 2, 2'-azino-bis (3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt (ABTS) and a reducing power assay. The total phenol content was also analyzed, and phenolic compounds were detected using HPLC/UV, whereas the inhibitory effect of Valeriana fauriei on oxidative DNA damage was measured using ${\phi}-174$ RF I plasmid DNA cleavage assay. The DPPH and ABTS radical scavenging activity were $75.17{\pm}3.55%$ and $95.83{\pm}0.63%$, repectively, and the reducing power was $93.14{\pm}1.74$ at $200{\mu}g/m{\ell}$. The total phenol content was $10.24{\pm}0.04mg/g$, whereas chlorogenic acid, catechin, caffeic acid and epicatechin were identified using HPLC/UV, and the ${\phi}-174$ RF I plasmid DNA cleavage assay indicated that V. fauriei provided protection against oxidative damage. Conclusions: The results of the present study suggest that V. fauriei has powerful antioxidant activity that can provide protective effects against the oxidative DNA damage caused by free radicals. The species, therefore, provides a valuable resource for the development of natural pharmaceutical to treat aging, cancer, and degenerative diseases.

• 미생물학회지
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• 제54권3호
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• pp.286-288
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• 2018

남자 대학생의 피부에서 분리한 Moraxella osloensis NP7는 베타-락탐과 아미노글리코사이드 항생제에 대해 내성을 보였다. 본 연구에서는 NP7 균주 유전체의 완전한 염기서열과 유전자 주석을 보고하고자 한다. NP7 균주는 원형 염색체와 7개의 플라스미드를 갖고 있다. 염색체는 43.9%의 G + C 함량을 갖는 2,389,582개의 염기쌍을 갖고 있으며, 단백질을 암호하는 2,065개의 유전자를 보유하고 있다. 전체 플라스미드는 평균적으로 40.5%의 G + C 함량을 갖는 654,202개의 염기쌍을 갖고 있으며, 단백질을 암호하는 667개의 유전자를 보유하고 있다. 염색체는 4개의 리보좀 RNA 오페론, 1개의 transfermessenger RNA 유전자, 47개의 tRNA 유전자, 3개의 핵산스위치 유전자 그리고 3개의CRISPR array를 포함하고 있으며, 1개의 CRISPR은 pNP7-1 플라스미드에 존재한다. 베타-락탐과 아미노글리코사이드 항생제에 내성을 부여하는 유전자는 pNP7-1 플라스미드에 존재하고 있다.

• 한국미생물·생명공학회지
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• 제50권1호
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• pp.63-70
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• 2022

Two small cryptic plasmids, pHG1 and pHG2, were isolated from Levilactobacillus zymae (formerly Lactobacillus zymae) GU240 and characterized. pHG1 is 1,814 bp in size with a GC content of 37.4% and contains two open reading frames. orf1 can potentially encode a protein of 101 amino acids (aa) with 99% identity with the copy number control protein of Lacticaseibacillus paracasei. orf2 can potentially encode a protein of 230 aa with 99% identity with a replication protein from multiple species. Six inverted repeats (IR I-VI) and six direct repeats (DR I-VI) were found in pHG1. pHG2 is 2,864 bp in size, with a GC content of 39.6%. pHG2 has two orfs. orf1 might encode a protein with 99% identity with the TrsL transmembrane protein. orf2 might encode a protein with 99% identity with plasmid recombination proteins from lactic acid bacteria. Both pHG1 and pHG2 may be useful as frames for constructing lactic acid bacteria-Escherichia coli shuttle vectors.

• 대한본초학회지
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• 제30권2호
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• pp.31-36
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• 2015

Objectives : In this study, we demonstrated the antioxidant activities and the inhibitory effect on oxidative DNA damage of ethyl acetate fractions extracted from Sophorae Flos and Sophorae fructus. Methods : Sophorae Flos and Sophorae fructus were extracted with methanol(MeOH) and divided to Petroleum ether, Ethyl acetate(EtOAC) and Water fraction. The antioxidant activities were conducted by the 1,1-diphenyl-2-picryl hydrazyl(DPPH) radical, 2, 2'-Azine-bis(3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt(ABTS) radical scavenging assay, $Fe^{2+}$ chelating assay and Reducing power assay. The inhibitory effect of DNA damage were characterized on ${\varphi}$ X-174 RF I plasmid DNA cleavage assay. In addition, we analyzed the Total phenol contents and the Vitamin C contents of Sophorae Flos and Sophorae fructus. Results : The results of DPPH were 92.71% and 94.72%, ABTS were 87.16% and 62.44%, and $Fe^{2+}$ chelating were 95.81% and 85.11% at $200{\mu}g/m{\ell}$ of Sophorae Flos and Sophorae fructus respectively. The Sophorae Flos showed stronger effect than Sophorae fructus in Reducing Power assay. Total phenol content was 111.77 mg/g and 122.54 mg/g, and Vitamin C content was 2.59 mg/g and 3.03 mg/g. Also both Sophorae Flos and Sophorae fructus have inhibitory antioxidant effect on ${\varphi}$ X-174 RF I plasmid DNA cleavage assay. Conclusions : Over all, this study suggests that Sophorae Flos and Sophorae fructus can be used as not only effective antioxidant but also natural medicine.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.771-774
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• 2001

NADPH has been known as a regulating factor the biosynthesis of polyhydroxyalkanote(PHA), and the flux of NADPH for PHA biosynthesis could be enforced by the amplification of zwf gene encoding glucose 6-phosphate dehydrogenase. The recombinant plasmid pCZWF harboring PHA synthase, phbC from R. eutropha and zwf from E. coli were constructed, and were transformed to R. eutropha by electroporation. The biosynthesis of P(3HB-3HV) copolymer were carried out in transformant R. eutropha through the two-stage cultivation method using valerate as a precursor. The biosynthesis rate and PHA content of transformant R. eutropha harboring pCZWF were increased compared with transformant R. eutropha harboring only phbC. Especially, the molar fraction of 3HV was increased from 68% to 74% due to amplification of zwf gene. And the biosynthesis P(3HB-3HV) and P(3HB-4HB) carried out using propionate and ${\gamma}-butyrolactone$ as a precursor, respectively. But the rate, content, and molar fraction of biosynthesis copolymers were not influenced appreciably. This may be due to the reduced availability of NADPH.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 1991년도 춘계학술발표대회 논문집
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• pp.225-236
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• 1991

The genes encoding the thermostable $\alpha$-amylase and maltogenic amylase from Bacillus lichenciformis were cloned and expressed in E. coli. The recombinant plasmid pTA322 was found to contain a 3.1kb EcoRI genomic DNA fragment of the thermostable $\alpha$-amylase. The cloned $\alpha$-amylase was compared with the B. licheniformis native $\alpha$-amylase. Both $\alpha$-amylase have the same optimal temperature of $70^{\circ}C$ and are stable in the pH range of 6 and 9. The complete nucleotide sequences of the thermostable $\alpha$-amylase gene were determined. It was composed of one open reading rame of 1,536 bp. Start and stop codons are ATG and TAG. From the amino acid sequence deduced from the nucleotide sequence, the cloned thermostable $\alpha$-amylase is composed of 483 amino acid residues and its molecular weight is 55,200 daltons. The content of guanine and cytosine is $47.46mol\%$ and that of third base codon was $53_41mol\%$. The recombinant plasmid, pIJ322 encoding the maltogenic amylase contains a 3.5kb EcoRI-BamHI genomic DNA fragment. The optimal reaction temperature and pH of the maltogenci amylase were $50^{\circ}C$ and 7, respectively. The maltogenic amylase was capable of hydrolysing pullulan, starch and cyclodextrin to produce maltose from starch and panose from pullulan. The maltogenic amylase also showed the transferring activity. The maltogenic amylase gene is composed of one open reading frame of 1,734bp. Start and stop codons are ATG and ATG. At 2bp upstream from start codon, the nucleotide sequence AAAGGGGGAA seems to be the ribosome-binding site(RBS, Shine-Dalgarno sequence). A putative promoter(-35 and-10 regions) was found to be GTTAACA and TGATAAT. From deduced amino acid sequence from the nucleotide srquence, this enzyme was comosed of 578 amino acid residues and its molecular weight was 77,233 daltons. The content of guanine and cytosine was $48.1mol\%$. The new recombinant plasmid, pTMA322 constructed by inserting the thermostable $\alpha$-amylase gene in the EcoRI site of pIJ322 to produce both the thermostable $\alpha$-amylase and the maltogenic amylase were expressed in the E. coli. The two enzymes expressed from E. coli containing pTMA322 was reacted with the $15\%$ starch slurry at $40^{\circ}C$ for 24hours. The distribution of the branched oligosaccharides produced by the single-step process was of the ratio 50 : 50 between small oligosaccharide up DP3 and large oligosaccharide above DP3.