토양으로부터 Myxobacteria의 분리 및 165 rDNA RFLP분석

김수광,최병현,김종균,이병규,강희일 한국미생물학회 2003 미생물학회지 Vol.39 No.3

토양 시료와 Coli-spot 한천평판 배지를 이용하여 myxobacteria를 분리하였다. 용균 현상이 관찰되는 Coli-spot 한천평판에서 myxobacteria의 swarm및 자실체 형성 여부를 확인하고, 확인된 자실체를 분리하여 VY/2 한천평판 배지에서 순수배양을 실시하였다. 분리 균주의 동정을 위하여 myxobacteria표준 균주 및 토양에서 분리한 균주들의 16S리보좀 DNA를 중합효소 연쇄 반응을 통해 증폭시킨 다음, 제한효소(HaeIII, EcoRI 및 EcoRV)로 절단하여 RFLP 양상을 비교하였다. 그 결과, 토양에서 분리한 균주들이 Family I, II, III의 myxobacteria에 속하는 것을 확인하였다. In an attempt to isolate myxobacteria from soil samples, we isolated swarm and fruiting body forming bacteria that have bacteriolytic activity on Coli-spot agar plate. For the classification of myxobacteria, 16S rDNA RFLP patterns were analyzed. Amplified 16S rDNAs of myxobacteria type strains (Family I, II, III and IV), negative control strains and soil-isolates were restricted with HaeIII, EcoRI and EcoRV, respectively. We found that the soil-isolates belongs to myxobacteria Family I, II, III.

Selection of KYC 3270, a Cellulolytic Myxobacteria of Sorangium cellulosum, against Several Phytopathogens and a Potential Biocontrol Agent against Gray Mold in Stored Fruit

Kim, Sung-Taek,Yun, Sung-Chul The Korean Society of Plant Pathology 2011 Plant Pathology Journal Vol.27 No.3

During 2002-2008 in Korea, 455 extracts from myxobacteria consisting of 318 cellulolytic and 137 bacteriolytic myxobacteria were isolated, which were then screened for antifungal activity against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Penicillium sp., Pyricularia grisea, and Phytophthora capsici. 204 isolates had antifungal activity, causing both a clear zone due to blocked spore germination and inhibition of mycelial growth; most (199) were from cellulolytic (Sorangium cellulosum) and only five were from bacteriolytic myxobacteria. B. cinerea, the best controlled among the five tested pathogens, had a unique group of antifungal isolates of myxobacterial extracts compared to the other pathogens' groups. Among seventy-nine bioactive myxobacteria, four isolates, KYC 3130, KYC 3247, KYC 3248 and KYC 3270, were selected and all were cellulolytic. Liquid culture filtrates of these four myxobacteria were applied to tomato, cherry tomato, strawberry, and kiwi fruits 5 h before inoculation with gray mold conidia; then the treated fruits were placed in an airtight container and the experiment was repeated six to eight times. Incidence (%) of gray mold on fruit of the infected control treatment was 84-98%, whereas it was only 5-21% after the KYC 3270 treatment. After KYC 3270 treatment of the four fruits, mold control was 79-95%, which was highest among the filtrates and statistically the same as treatment with fludioxonil, a registered chemical against gray mold of stored fruits.

Selection of KYC 3270, a Cellulolytic Myxobacteria of Sorangium cellulosum, against Several Phytopathogens and a Potential Biocontrol Agent against Gray Mold in Stored Fruit

김성택,윤성철 한국식물병리학회 2011 Plant Pathology Journal Vol.27 No.3

During 2002−2008 in Korea, 455 extracts from myxobacteria consisting of 318 cellulolytic and 137 bacteriolytic myxobacteria were isolated, which were then screened for antifungal activity against the phytopathogens Botrytis cinerea, Colletotrichum acutatum, Penicillium sp., Pyricularia grisea, and Phytophthora capsici. 204isolates had antifungal activity, causing both a clear zone due to blocked spore germination and inhibition of mycelial growth; most (199) were from cellulolytic (Sorangium cellulosum) and only five were from bacteriolytic myxobacteria. B. cinerea, the best controlled among the five tested pathogens, had a unique group of antifungal isolates of myxobacterial extracts compared to the other pathogens’ groups. Among seventy-nine bioactive myxobacteria, four isolates, KYC 3130, KYC 3247, KYC 3248 and KYC 3270, were selected and all were cellulolytic. Liquid culture filtrates of these four myxobacteria were applied to tomato, cherry tomato,strawberry, and kiwi fruits 5 h before inoculation with gray mold conidia; then the treated fruits were placed in an airtight container and the experiment was repeated six to eight times. Incidence (%) of gray mold on fruit of the infected control treatment was 84−98%,whereas it was only 5−21% after the KYC 3270 treatment. After KYC 3270 treatment of the four fruits,mold control was 79−95%, which was highest among the filtrates and statistically the same as treatment with fludioxonil, a registered chemical against gray mold of stored fruits.

Screening of Myxobacteria Carrying Tubulysin Biosynthetic Genes

( Hyesook Hyun ),( Juo Choi ),( Daun Kang ),( Yungpil Kim ),( Pilgoo Lee ),( Gregory J. Y. Chung ),( Kyungyun Cho ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 한국미생물·생명공학회지 Vol.49 No.1

Tubulysins are a group of secondary metabolites produced by myxobacteria that inhibit the function of the eukayotic cytoskeleton. We developed a pair of PCR primers that specifically amplified tubulysin biosynthetic genes. Using these primers, eight out of the eighty-one strains of myxobacteria belonging to the Cystobacteraceae family that harbored putative tubulysin biosynthetic genes were screened through PCR analysis. The selected strains included two Archangium gephyra, two Stigmatella sp., two Vitiosangium cumulatum, and two unidentified myxobacteria. LC-MS analysis of the culture extracts from the selected strains revealed that A. gephyra KYC4066 produced putative tubulysin A and B.

국내토양에서 분리한 점액세균의 동정및 특성

김재헌,손승렬 한국미생물학회 2001 미생물학회지 Vol.37 No.4

We isolated a Myxobacteria strain from a soil sample obtained from Mt. Daedoon located in Choongnam, Korea. This strain, ARJ, secreted slime while swarmed on the surface of CT medium. It produced greenish yellow pigment in liquid or solid media, and the swarming edge showed green florescence under U. V. at 366 nm. It formed fruiting bodies when nutrient was exhausted, which is one of the most imkportant characteristics of Myxobacteria. The fruiting bodies did not have a stalk and consisted of naked myxospores when examined under the scanning electron microscope. These traits lead us to believe that this strain is very close to Myxococcus virescens. It showed antimicrobial activity, especially against Gram positive bacteria. Culture filtrate showed the activity but this was not due to protein. The culture filtrate also had proteolytic activity in which at least two enzymes are involved. 충남 대둔산의 토양으로부터 분리한 점액세균을 ARJ라 명명하고 그 특성을 알아보았다. CT 배지에서 swarming을 하며 성장한 이 균주는 slime을 형성하였고, 액체 및 고체배지 상에서 황록색의 색소를 방출하였으며 swarming 부분을 파장이 366 nm인 자외선으로 조사하였을 때 초록색의 형광을 띄었다. 또한 이 균주는 영양분이 고갈되었을 때 fruiting body를 형성하는 것으로 보아 Myxobacteria라고 생각되었으며 주사전자 현미경 관찰 결과 이 균주가 형성한 fruiting body는 stalk이 없었고 naked myxospore를 가지고 있었다. Myxobacteria의 분류에 있어서 가장 중요한 이러한 형태학적 특성들로 볼때 이 균주는 Myxococcus virescens와 가장 유사한 것으로 밝혀졌다. 한편 이 균주는 특히 gram 양성 세균에 대해 antimicrobial activity가 있는 것으로 나타났는데, 여과한 배양 여액에서도 이렇ㄴ activity가 있었지만 비변성 polyacrylamide 전기영동을 하여 본 결과 이 물질이 단백질은 아닌 것으로 밝혀졌다. 또한 이 배양 여액은 상당한 proteolytic activity가 있었으며 최소한 2개의 proteolytic enzyme이 있는 것으로 비변성 polyacrylamide 전기영동을 통하여 밝혀졌다.

아산시와 우포늪 토양의 점액세균 다양성

정진우,김진우,조경연,Chung, Jin-Woo,Kim, Jin-Woo,Cho, Kyung-Yun 한국미생물학회 2010 미생물학회지 Vol.46 No.4

점액세균의 16S rDNA에 특이적으로 부착하는 프라이머를 사용한 중합효소연쇄반응(PCR)을 통해 아산시와 우포늪에서 채취한 다섯 토양시료 내 점액세균의 다양성을 조사하였다. 점액세균의 16S rDNA을 갖는 76개 PCR 조각의 서열분석 결과, 표준균주와 95% 미만의 상동성을 보이는 5개의 신속 추정 점액세균이 관찰되어 국내 토양에 아직까지 분리되지 않은 많은 새로운 점액세균들이 존재함을 보여주었다. Diversity of myxobacteria in five soil samples from Asansi and Uponeup in Korea was explored by means of polymerase chain reaction (PCR) using primers that specifically bind 16S rDNA of myxobacteria. DNA sequence analysis of 76 PCR fragments containing myxobacterial 16S rDNA revealed five putative novel myxobacterial genera whose 16S rDNA sequences shared <95% sequence identity with those of the type strains. This finding indicates the presence of many uncultured and unidentified myxobacterial species in Korean soil.

유전자조작, 균주분리 Myxobacteria의 Proteolytic Activity 특성

김재영 ( Jae Young Kim ),정진우 ( Jin Woo Chung ),조경연 ( Kyung Yun Cho ),이용섭 ( Yong Sub Yi ) 한국미생물생명공학회 2009 한국미생물·생명공학회지 Vol.37 No.3

Myxobacteria의 생리활성 물질

김용석 ( Yong Seok Kim ),배우철 ( Woo Chul Bae ),백성진 ( Seong Jin Baek ) 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 2003 한국미생물·생명공학회지 Vol.31 No.1

Cellulase 유전자 염기서열에 기초한 Sorangium cellulosum 균주들의 계통분류

이한빛 ( Han Bit Lee ),윤진권 ( Jin Kwon Youn ),조경연 ( Kyung Yun Cho ) 한국미생물생명공학회(구 한국산업미생물학회) 2011 한국미생물·생명공학회지 Vol.39 No.1

두 개의 cellulase 유전자 xynB1, bglA2과 groEL1 유전자 염기서열에 기초하여 국내에서 분리한 34균주의 Sorangium cellulosum 균주들을 계통 분석한 결과, 점액세균 중 가장 많은 생리활성물질이 발견된 종인 S. cellulosum 내에는 최소한 5그룹의 소그룹이 존재함을 보였다. 이 분석은 또한 S.cellulosum 균주들의 다양성을 보여주어 분석한 34균주 중 30균주가 서로 다른 균주인 것으로 나타났다. Phylogenetic analysis of two cellulase genes, xynB1 and bglA2, and the groEL1 gene from 34 Sorangium cellulosum strains isolated in Korea suggested that there are at least five subgroups in S. ellulosum, which is the most proficient producer of secondary metabolites among myxobacteria. This analysis also revealed diversity among the isolated S. cellulosum. It appeared that at least 30 out of 34 strains are different each other.

Discovery of Argyrin-Producing Archangium gephyra MEHO_001 and Identification of Its Argyrin Biosynthetic Genes

( Juo Choi ),( Taejoon Park ),( Daun Kang ),( Jeongju Lee ),( Yungpil Kim ),( Pilgoo Lee ),( Gregory J. Y. Chung ),( Kyungyun Cho ) 한국미생물 · 생명공학회 2021 한국미생물·생명공학회지 Vol.49 No.4

Argyrins are a group of anticancer and antibacterial octapeptide bioactive substances isolated from myxobacteria. In this study, we showed that the myxobacterium Archangium gephyra MEHO_001, isolated in Korea, produces argyrins A and B. MEHO_001 cells tend to aggregate when cultured in liquid media. Hence, a dispersion mutant, MEHO_002, was isolated from MEHO_001. The MEHO_002 strain produced approximately 3.5 times more argyrins than that produced by the wild-type strain MEHO_001. We determined the whole-genome sequence of A. gephyra MEHO_002 and identified a putative argyrin biosynthetic gene cluster comprising five genes, arg1-arg5, encoding non-ribosomal peptide synthases and tailoring enzymes. Inactivation of arg2 by plasmid insertion disrupted argyrin production. The amino acid sequences of the proteins encoded by arg2-arg5 of A. gephyra MEHO_002 were 90-98% similar to those encoded by the argyrin biosynthetic genes of Cystobacter sp. SBCb004, an argyrin-producing myxobacterium with identical domain organization.