• 한국미생물·생명공학회지
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• 제50권1호
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• pp.81-88
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• 2022

Acetic acid bacteria (AAB) are versatile organisms involved in the production of variety of fermented foods, such as vinegar and kombucha, and products of biotechnological relevance, such as bacterial cellulose. In the present study, Malatya apricot, a variety with protected designation of origin (PDO), and vinegar samples produced using various fruits were used to isolate AAB. The 19 AAB isolates obtained were typed using (GTG)5 fingerprinting, and the ones selected were identified by sequencing either 16S rDNA alone or in combination with 16S-23S rRNA internal transcribed spacer region or ligA gene. While all apricot isolates (n = 10) were Gluconobacter cerinus, vinegar isolates (n = 9) were composed of Komagataeibacter saccharivorans, Acetobacter syzygii, and possible two new species of AAB, Komagataeibacter sp., and Gluconobacter sp. (GTG)5 fingerprinting showed the presence of several genotypes of G. cerinus in the apricot samples. Screening for some technologically relevant properties, including thermotolerance, ethanol tolerance, and cellulose production capability, showed that all Komagataeibacter and some Gluconobacter isolates could tolerate the temperature of 35℃, and that vinegar isolates could tolerate up to 8% ethanol. One isolate, Komagataeibacter sp. GUS3 produced bacterial cellulose (1 g/l) and has the potential to be used for cellulose production.

• The Plant Pathology Journal
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• 제23권2호
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• pp.90-96
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• 2007

To overcome the problem of the yield reduction due to the viral satellite mediated protection, a culture mix of three nitrogen-fixing bacteria species of the genus Azospirillum (A. brasilienses N040, A. brasilienses SP7, and A. lipoferum MRB16), and one strain of cyanobacteria (Anabena oryzae Fritsch) were utilized as biofertilizer mixture in both greenhouse and field experiments. When protected plants were treated with biofertilizer mixtures, the fruit yield of biofertilized plants increased by 48% and 40% in a greenhouse and field experiment, respectively, compared to untreated plants inoculated with the protective viral strain alone. Polyacrylamide gel electrophoresis (PAGE) analysis of total nucleic acid (TNA) extracts revealed that biofertilization did not affect the accumulation of the viral satellite RNA (CARNA 5) that is required for plant protection against other destructive viral strains of CMV. The yield increment was a good compensation for the yield loss caused by the use of the protective viral strain associated with CARNA 5.

• Journal of Species Research
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• 제6권2호
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• pp.91-100
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• 2017

Five bacterial strains, ES10-3-3-1, KKM10-2-2-1, Ant11, JM10-4-1-3, and KMS4-11 assigned to the genus Deinococcus were isolated from soil samples collected from Namyangju-si in Gyeonggi-do, Gangnam-gu and Dongdaemun-gu in Seoul, Korea. In addition, four bacterial strains, KKM10-2-7-2, JM10-2-5, JM10-2-6-2, and KKM10-2-3 assigned to the genus Hymenobacter were isolated from soil samples collected from Gangnam-gu and Dongdaemun-gu in Seoul, in South Korea. The five Deinococcus species were Gram-stain positive, pink-pigmented, and short-rod or coccus shaped. The four Hymenobacter species were Gram-stain negative, red-pigmented, and short-rod shaped. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains ES10-3-3-1, KKM10-2-2-1, Ant11, JM10-4-1-3, and KMS4-11 were most closely related to Deinococcus citri $NCCP-154^T$ (with 99.8% similarity), Deinococcus grandis DSM $12784^T$ (99.0%), Deinococcus marmoris DSM $12784^T$ (98.8%), Deinococcus claudionis $PO-04-19-125^T$ (98.7%), and Deinococcus radioresistens $8A^T$ (99.8%), respectively. KKM10-2-7-2, JM10-2-5, JM10-2-6-2, and KKM10-2-3 were most closely related to Hymenobacter algoricola $VUG-A23a^T$ (99.1% similarity), Hymenobacter elongatus $VUG-A112^T$ (99.1% similarity), Hymenobacter gelipurpurascens $Txg1^T$ (99.1% similarity), and Hymenobacter psychrotolerans $Tibet-IIU11^T$ (99.3% similarity), respectively. These nine species have never been reported in Korea; thus, five Deinococcus species are reported in the family Deinococcaceae, order Deinococcales, class Deinococci, phylum Deinococcus-Thermus and four Hymenobacter species are reported in the family Cytophagaceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes.

• Tuberculosis and Respiratory Diseases
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• 제78권4호
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• pp.432-435
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• 2015

This is a report of the first South Korean case of a lung disease caused by Mycobacterium simiae. The patient was a previously healthy 52-year-old female. All serial isolates were identified as M. simiae by multi-locus sequencing analysis, based on hsp65, rpoB, 16S-23S rRNA internal transcribed spacer, and 16S rRNA fragments. A chest radiography revealed deterioration, and the follow-up sputum cultures were persistently positive, despite combination antibiotic treatment, including azithromycin, ethambutol, and rifampin. To the best of our knowledge, this is the first confirmed case of a lung disease caused by M. simiae in South Korea.

• Genomics & Informatics
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• 제1권1호
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• pp.50-54
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• 2003

Genome of an extreme thermophile, Thermus caldophilus GK24 has been analyzed to construct the genomic map. The genomic DNAs encapsulated in agarose gel were digested with SspI, EcoRI, SpeI, and HpaI restriction endonucleases, and then the resulting genomic DNA fragments were analyzed by pulsed-field gel electrophoresis. Its restriction map has been constructed by analyzing sizes of the restriction fragments obtained from both complete and partial digestions. The circular form of its genome was composed of about 1.98 Mbp and a megaplasmid. The genomic loci for the genes of xylose isomerase, thioredoxin, tRNA-16S rRNA, 23S rRNA, L5 ribosomal protein, ADP-glucose pyrophosphorylase, DNA-ligase, and Tca DNA polymerase were determined by both Southern hybridization and PCR.

• Journal of Microbiology and Biotechnology
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• 제33권11호
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• pp.1448-1456
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• 2023

A Gram-positive, non-motile, and non-spore-forming lactic acid bacterium, designated as BK2^T, was isolated from kimchi, a Korean traditional fermented vegetable food, and the taxonomic characteristics of strain BK2^T, along with strain LMG 11983, were analyzed. Both strains optimally grew at 30℃, pH 7.0, and 1.0% NaCl. Cells of both strains were heterofermentative and facultatively anaerobic rods, demonstrating negative reactions for catalase and oxidase. Major fatty acids (>10%) identified in both strains were C_18:1 ω9c, C_16:0, and summed feature 7 (comprising C_19:1 ω6c and/or C_19:1 ω7c). The genomic DNA G+C contents of both strains were 44.7 mol%. The 16S rRNA gene sequence similarity (99.9%), average nucleotide identity (ANI; 99.9%), and digital DNA-DNA hybridization (dDDH; 99.7%) value between strains BK2^T and LMG 11983 indicated that they are different strains of the same species. Strain BK2^T was most closely related to Weissella confusa JCM 1093^T and Weissella cibaria LMG 17699^T, with 100% and 99.4% 16S rRNA gene sequence similarities, respectively. However, based on the ANI and dDDH values (92.3% and 48.1% with W. confusa, and 78.4% and 23.5% with W. cibaria), it was evident that strain BK2^T represents a distinct species separate from W. confusa and W. cibaria. Based on phylogenetic, phenotypic, and chemotaxonomic features, strains BK2^T and LMG 11983 represent a novel species of the genus Weissella, for which the name Weissella fermenti sp. nov. is proposed. The type of strain is BK2^T (=KACC 22833^T=JCM 35750^T).

• 한국미생물·생명공학회지
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• 제49권3호
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• pp.374-383
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• 2021

Rhizoctonia solani is one of the major pathogens that cause sheath blight disease in rice. Sheath blight is one of the most difficult diseases to control. Biological control (with the use of rhizobacteria) is one of the ways to control this disease. Plant Growth Promoting Rhizobacteria (PGPR) is a rhizosphere bacterium that can be used to enhance plant growth. The composition of the rhizobacteria in organic and nonorganic soil is affected by the chemical characteristics of the soil - which influences plant physiology and root exudation patterns. This study aimed to obtain a species of rhizobacteria which shows PGPR activity, from organic and nonorganic rice fields and test their capability to suppress R. solani growth. Out of 23 isolates screened for PGPR activity, the following isolates showed high PGPR activity and were selected for in vitro antagonistic activity testing against R. solani: ISO6, ISO11, ISO15, ISN2, ISN3, and ISN7, The six isolates produced 43,42-75,23 ppm of IAA, possessed phosphorus solubilization capability, and chitinase-producing activity. ISO6 (54.88%) and ISN7 (83.33%) displayed high inhibition capacities against R. solani, in vitro. ISO6 and ISN7 inhibited the growth of R. solani lesions on rice leaves by 89% and 100% (without lesion), respectively, after 7 days of incubation. Analysis of their 16S rRNA sequences revealed that the ISO6 isolate was Citrobacter freundii and ISN7 isolate was Pseudomonas aeruginosa.

• Journal of Dairy Science and Biotechnology
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• 제37권2호
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• pp.115-128
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• 2019

본 연구는 전통 김치로부터 유단백질 분해능과 lactose 분해능을 가지는 유산균을 선발하고, 프로바이오틱 활성을 측정하여 발효유용 스타터로서의 이용가능성을 조사하였다. BCP agar에서 젖산생성력이 우수한 32 colony를 선발한 후 내산성 및 내담즙성 모두에서 90% 이상으로 내성이 우수한 2 colony(KC23, KF26)를 2차로 선발하였다. 이들을 대상으로 API 50CHL 탄수화물 이용성 테스트 및 16S rRNA 염기서열을 분석한 결과, L. plantarum KC23과 L. paracasei KF26으로 동정되었다. 이들 중 lactose와 raffinose를 포함하여 당분해능을 가진 L. plantarum KC23을 최종 선발하고 프로바이오틱 활성을 조사하였다. 우유단백질 분해능을 10% 환원탈지유 배양 중의 유리 tyrosine 함량으로 측정한 결과, 배양 8시간 후에는 $24.1{\mu}g/mL$에서 배양 16시간 후에는 $43.9{\mu}g/mL$로 급격하게 증가되었으며, 또한 clear zone형성 크기를 비교한 결과 12 mm로 상업균주인 L. acidophilus CSLA의 9 mm보다 우수한 특성을 보였다. 온도별 생장특성을 확인한 결과는 $45^{\circ}C$에서 보다 $35^{\circ}C$에서 잘 증식하는 중온균의 특성을 나타내었고, $37^{\circ}C$에서 12시간 동안 배양한 결과 배양 6-10시간 사이에 대수증식기를 보였으며, 배양 12시간 후 생균수는 $8.9{\times}10^8CFU/mL$와 pH 4.25 수준을 나타내었다. 항균활성을 측정한 결과는 5개 병원성균에 대하여 8-13 mm의 clear zone을 형성하여 우수한 저해특성을 보였으며, 그중 Salmonella typhimurium과 Bacillus cereus에 대한 항균활성이 가장 우수하였다. 장내부착능을 측정한 결과는 비교균주인 LGG에 비하여 2.23배의 우수한 결과를 보였으며, 10% 환원탈지유를 이용한 $37^{\circ}C$ 배양에서 젖산생성능을 확인한 결과는 대조군인 L. acidophilus CSLA에 비하여 다소 낮은 경향을 보였지만, 적정산도가 0.74% 수준으로서 저산성 발효유 제조를 위한 스타터로 활용 가능할 것으로 판단되었다.

• Journal of Microbiology and Biotechnology
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• 제31권9호
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• pp.1210-1217
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• 2021

Two gram-negative, catalase-positive, strictly aerobic, and white colony-forming bacteria, strains H242^T and B156^T, were isolated from soil in South Korea. Cells of strain H242^T were oxidase-positive and non-motile short rods, while those of strain B156^T were oxidase-negative and long non-motile rods. Ubiquinone-8 was identified as the sole isoprenoid quinone in both strains. C_16:0, cyclo-C_17:0, andsummed feature 3 (C_16:1 ω7c and/or C_16:1 ω6c) and phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol were identified in both strains as the major cellular fatty acids and polar lipids, respectively. The DNA G+C contents of strains H242^T and B156^T were 69.4 mol% and 69.3 mol%, respectively. Phylogenetic analyses based on 16S rRNA and 92 concatenated core gene sequences revealed that strains H242^T and B156^T formed distinct phylogenic lineages from other Ramlibacter type strains. The DNA-DNA hybridization (DDH) value between strains H242^T and B156^T was 24.6%. Strains H242^T and B156^T were most closely related to Ramlibacter ginsenosidimutans BXN5-27^T and Ramlibacter monticola G-3-2^T with 98.4% and 98.6% 16S rRNA gene sequence similarities, respectively. Digital DDH values between strain H242^T and R. ginsenosidimutans and between strain B156^T and R. monticola were 23.5% and 26.1%, respectively. Phenotypic, chemotaxonomic, and molecular analyses indicated that strains H242^T and B156^T represent two novel species of the genus Ramlibacter, for which the names Ramlibacter terrae sp. nov. and Ramlibacter montanisoli sp. nov., respectively, are proposed. The type strains of R. terrae and R. montanisoli are H242^T (=KACC 21667^T=JCM 33922^T) and B156^T (=KACC 21665^T=JCM 33920^T), respectively.

• 생명과학회지
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• 제27권6호
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• pp.688-693
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• 2017

하수 슬러지로부터 감자 뿌리썩음병 및 토마토 탄저병을 유발하는 Colletotrichum coccodes에 대해 항진균 활성이 있는 세균을 분리하였다. 분리균의 partial 16S rRNA sequence는 Bacillus methylotrophicus CBMB205 및 Bacillus amyloliquefaciens subsp. plantarum FZB42와 각각 99%의 상동성을 보여주었다. 분리균은 neighbor-joining phylogenetic tree, BlastN 염기서열 분석, 형태학적 및 배양학적 특성에 따라 Bacillus sp. SW29-2로 동정하였다. 분리균 Baciilus sp. SW29-2는 B. methylotrophicus CBMB205 type strain과 비교시 4% 이상 NaCl에서 생육하는 것이외에 형태학적, 생리학적 특성이 모두 동일하였다. 분리은 호기성, Gram-양성, 내생포자를 형성하는 세균이었다. 실험한 $18-47^{\circ}C$(최적, 약 $38^{\circ}C$)의 온도범위에서, pH 3-9(최적, 약 6.0) 범위의 초기 배지 pH에서 모두 생육이 관찰되었다. Baciilus sp. SW29-2의 C. coccodes에 대한 생육저지환(직경)은 23 mm에서 29 mm의 범위이었다. 분리 세균은 또한 사과 푸른곰팡이병(penicillum rot disease)을 유발하는 Penicillium expansum에 대해 우수한 항진균 활성을 보여주었다. 현재까지, Bacillus속 세균의 C. coccodes에 대한 항균활성 연구는 파악할 수 없었다. 이 결과는 분리균 Bacillus sp. SW29-2가 식물 병원성 C. coccodes에 대해 생물학적 방제제로의 활용 가능성이 있으며, 추후, 식물병을 유발하는 다른 진균에 대해서 적용할 예정이다.