• Title/Summary/Keyword: environmental microbiology

Search Result 1,796, Processing Time 0.03 seconds

A report of 26 unrecorded bacterial species in Korea, belonging to the Bacteroidetes and Firmicutes

  • Kim, Haneul;Yoon, Jung-Hoon;Cha, Chang-Jun;Seong, Chi Nam;Im, Wan-Taek;Jahng, Kwang Yeop;Jeon, Che Ok;Kim, Seung Bum;Joh, Kiseong
    • Journal of Species Research
    • /
    • v.5 no.1
    • /
    • pp.166-178
    • /
    • 2016
  • An outcome of the study to discover indigenous prokaryotic species in Korea, a total of 26 bacterial species assigned to the classes Bacteroidetes and Firmicutes were isolated from diverse environmental samples collected from soil, tidal flat, freshwater, seawater, wetland, plant roots, and fermented foods. From the high 16S rRNA gene sequence similarity (>99.0%) and formation of a robust phylogenetic clade with the closest species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that these 26 species have been described in Korea; therefore 14 strains for the order Flavobacteriales and two strains for the order Cytophagales were assigned to the class Bacteroidetes, and 8 strains for the order Bacillales and 4 strains for the order Lactobacillales were assigned to the class Firmicutes are reported for new bacterial species found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are also described in the species description section.

Transformation of Metarhizium anisopliae by using pBRG-4 (pBRG-4를 이용한 Metarhizium anisopliae의 형질전환)

  • Lee, Dong-Gyu;Yeh, Wan-Hae;Hwang, Cher-Won;Kwon, Suk-Tae;Kang, Sun-Chul
    • Applied Biological Chemistry
    • /
    • v.41 no.3
    • /
    • pp.219-223
    • /
    • 1998
  • We have established a transformation system for entomopathogenic fungus, Metarhizium anisopliae, in order to develop mycoinsecticide by recombinant DNA techniques. Protoplasts of M. anisopliae would be transformed to a benomyl-resistant by introducing pBRG-4 plasmid DNA, which contains a ${\beta}-tubulin$ gene of Aspergillus flavus conferring resistance to benomyl and a pyr4 gene of Neurospora crassa, in the presence of 5% polyethylene glycol and 10 mM calcium chloride. Transformants occuring at a frequency of 10 colonies per $50\;{\mu}g$ pBRG-4 DNA grew on the $5\;{\mu}g/ml$ concentrations of benamyl, while the wild type was inhibited by $2.5\;{\mu}g/ml$. From the Southern analysis using genomic DNAs isolated from M. anisopliae transformants, the positive signals suggested that the ${\beta}-tubulin$ gene had integrated in the M. anisopliae genome by homologous recombination.

  • PDF

A report of 34 unrecorded bacterial species in Korea, belonging to the Actinobacteria

  • Ko, Kwan Su;Cha, Chang-Jun;Im, Wan-Taek;Kim, Seung-Bum;Seong, Chi-Nam;Bae, Jin-Woo;Jahng, Kwangyeop;Cho, Jang-Cheon;Joh, Ki-seong;Lee, Soon Dong
    • Journal of Species Research
    • /
    • v.6 no.1
    • /
    • pp.1-14
    • /
    • 2017
  • As a subset study to discover indigenous prokaryotic species in Korea in 2014, a total of 34 bacterial strains assigned to the phylum Actinobacteria were isolated from various environmental samples collected from activate sludge, biotite, freshwater, gut of marine organisms, mud flat, sediment, soil, spent mushroom compost and sea water. On the basis of high 16S rRNA gene sequence similarity and a tight phylogenetic association with the closest species, it was revealed that each strain was assigned to independent and previously described bacterial species, with the exception of one isolate. There is no official report that these 34 species included in the phylum Actinobacteria have been described in Korea: 6 species of 5 genera in the order Corynebacteriales, 1 species of 1 genus in the order Frankiales, 2 species of 2 genera in the Micromonosporales, 14 species of 10 genera in Micrococcales, 2 species of 2 genera in the Propionibacteriales, 1 species of 1 genus in the Pseudonocardiales, 4 species of 2 genera in the Streptomycetales, 2 species of 2 genera in the Streptosporangiales and 1 species of 1 genus in the Solirubrobacterales. Gram reaction, cell and colony morphology, pigmentation, physiological characteristics, isolation sources and strain IDs are described in the section of species description.

Description of 39 unrecorded bacterial species in Korea, belonging to the class Alphaproteobacteria

  • Siddiqi, Muhammad Zubair;Kim, Seung-Bum;Cho, Jang-Cheon;Yoon, Jung-Hoon;Joh, Ki-seong;Seong, Chi-Nam;Bae, Jin-Woo;Jahng, Kwang-Yeop;Jeon, Che-Ok;Im, Wan-Taek
    • Journal of Species Research
    • /
    • v.6 no.2
    • /
    • pp.141-153
    • /
    • 2017
  • During an investigation of the biodiversity of bacterial species in Korea, we discovered many indigenous prokaryotic species. A total of 39 bacterial strains in the class Alphaproteobacteria were isolated from various environmental samples collected from marine organisms, sea water, fresh water, tap water, mud flats, activated sludge, mineral water, tidal flats, soil and decayed plants. From the high 16S rRNA gene sequence similarity (>98.7%) and formation of robust phylogenetic clades with the most closely related species, it was determined that each strain belonged to each independent and predefined bacterial species. There is no official report that any of these 39 Alphaproteobacteria species have been described in Korea. Specifically, 18 species in 11 genera in the order Sphingomonadales, 11 species in 10 genera in the order Rhizobiales, two species in two genera in the order Caulobacterales, six species in six genera in the order Rhodobacterales and two species in two genera in the order Rhodospirillales were found in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are described in the species description section.

A report of 29 unrecorded bacterial species belonging to the phylum Bacteroidetes in Korea

  • Cho, Sang Hyun;Yoon, Jung-Hoon;Kim, Seung-Bum;Jahng, Kwang-Yeop;Cho, Jang-Cheon;Joh, Ki-seong;Cha, Chang-Jun;Seong, Chi-Nam;Bae, Jin-Woo;Im, Wan-Taek;Jeon, Che Ok
    • Journal of Species Research
    • /
    • v.6 no.2
    • /
    • pp.119-128
    • /
    • 2017
  • Within a comprehensive, widescale investigation of indigenous prokaryotic species in Korea, 29 bacterial strains in the phylum Bacteroidetes were isolated from diverse environmental habitats that included soil, plant roots, natural caves, tidal flats, freshwater from lakes, and seawater. Based on their high 16S rRNA gene sequence similarities (>99.1%) and the formation of robust phylogenetic clades with the closest type species, each strain likely belonged to an independent and predefined bacterial species. There are no publications or official reports of the isolation of these 29 species in Korea. Our study provides strong evidence that seven species in three genera in the order Cytophagales, 15 species in 13 genera in the order Flavobacteriales and seven species in five genera in the order Sphingobacteriales, all within the phylum Bacteriodetes, are new reports of bacterial species in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are described in the species description section.

A report of 31 unrecorded bacterial species belonging to the class Alphaproteobacteria in Korea

  • Kim, Kyung Hyun;Yoon, Jung-Hoon;Kim, Seung-Bum;Jahng, Kwang-Yeop;Cho, Jang-Cheon;Joh, Ki-seong;Cha, Chang-Jun;Seong, Chi-Nam;Bae, Jin-Woo;Im, Wan-Taek;Jeon, Che Ok
    • Journal of Species Research
    • /
    • v.6 no.2
    • /
    • pp.129-140
    • /
    • 2017
  • During a comprehensive investigation of indigenous prokaryotic species in Korea, a total 31 bacterial strains assigned to the class Alphaproteobacteria were isolated from diverse environmental habitats including freshwater, seawater, brackish water, ginseng soil, plant roots, natural caves, and tidal flats. Based on their high 16S rRNA gene sequence similarities(>99.1%) and formation of robust phylogenetic clades with the closest type species, each strain was assigned to an independent and predefined bacterial species. Because there were no published or official reports regarding the isolation of these 31 species in Korea, this study identified three species in two genera in the order Caulobacterales, 12 species in 10 genera in the order Rhodobacterales, three species in two genera in the order Rhizobiales, two species in two genera in the order Rhodospirillales and 11 species in seven genera, all in the order Sphingomonadaceae within the Alphaproteobacteria are reported as new alphaproteobacterial species in Korea. Gram reaction, colony and cell morphology, basic biochemical characteristics, isolation source, and strain IDs are described in the species description section.

Characterization and Numerical Taxonomy of Heterotrophic Bacterial Community in Naktong Estuarine Ecosystem (낙동강 하구 생태계의 종속영양세균의 군집구조 분석 및 수리학적 분류)

  • 귄오섭;조경제
    • Korean Journal of Microbiology
    • /
    • v.30 no.6
    • /
    • pp.444-449
    • /
    • 1992
  • A total of 858 heterotrohic bacteria were isolated and analyzed hy numerical method to investigate the heterotrophic hacterial community structure in Naktong Estuary. Although the values of H' (Shannon's diversity index). ranged between 1.54 and 3.49. were similar with those of the data hefore the construction of Naktong River barrage, however J' (evenness index. 0.31-0.80) was reduced. Physiological tolerance index for water temperature ($P_{s}$) was high at St.l and 2 whose depthes arc shallower than the other stations. and indices for pH ($P_{h}$) and salinity ($P_{s}$) were high at St. 2. 3. 4 where freshwater and seawater arc mixed. The predominant clusters were identified as Aeromonas. Vihrio. Pseudomonas. Acinelobacter-Morexella. Alcaligenes. Flavobacterium. Micrococcaccae. and Enterohacteriaceae. The kinds nf the isolates were similar with the previous result. hut the dominant genus was changed. These results suggest that the environmental changes in Naktong Estuary affect the hacterial physiological adaptation rather than the composition of heterotrophic hactcrial community.

  • PDF

Stress-shock Response of a Methylotrophic Bacterium Methylovorus sp. strain SSl DSM 11726

  • Park, Jong H.;Kim, Si W.;Kim, Eungbin;Young T. Ro;Kim, Young M.
    • Journal of Microbiology
    • /
    • v.39 no.3
    • /
    • pp.162-167
    • /
    • 2001
  • Methylovorus sp. strain SS1 DSM 11726 was found to grow continuously when it was transferred from 30$\^{C}$ to 40$\^{C}$ and 43$\^{C}$. A shift in growth temperature from 30$\^{C}$ to 45$\^{C}$, 47$\^{C}$ and 50$\^{C}$ reduced the viability of the cell population by more than 10$^2$, 10$^3$and 10$\^$5/ folds, respectively, after 1h cultivation. Cells transferred to 47$\^{C}$ and 50$\^{C}$ after preincubation for 15 min at 43$\^{C}$, however, exhibited 10-fold increase in viability. It was found that incubation for 15 min at 40$\^{C}$ of Methylovorus sp. strain SSl grown at 30$\^{C}$ was sufficient to accelerate the synthesis of a specific subset of proteins. The major heat shock proteins had apparent molecular masses of 90, 70, 66, 60, and 58 kDA. The 60 and 58 kDa proteins were found to cross-react with the antiserum raised against GroEL protein. The heat shock response persisted for over 1h. The shock proteins were stable for 90 min in the cell. Exposure of the cells to methanol induced proteins identical to the heat shock proteins. Addition of ethanol induced a unique protein with a molecular mass of about 40 kDa in addition to the heat-induced proteins. The proteins induced in paraquat-treated cells were different from the heat shock proteins, except the 70 and 60 kDa proteins.

  • PDF

Microbial detection on pill types of herbal medicine in South Korea (국내 유통 중인 환약의 미생물 검출수준)

  • Ko, Gwang-Pyo;Shin, Heon-Tae
    • Journal of Society of Preventive Korean Medicine
    • /
    • v.15 no.3
    • /
    • pp.153-162
    • /
    • 2011
  • Objectives : This study has aimed to monitor microbial detection on pill types of herbal medicine which are circulating in markets including Oriental Medical Clinics(O.M.C.s) and Pharmacy in Korea. Methods : 10 different samples of O.M.Cs and 10 different samples of Pharmacy were investigated by culture method and non-culture method based on the 9th edition of microbial examination released by Korea Food & Drug Administration. Results : The total microbial count among each 10 samples were detected within the limit suggested by WHO. 2 samples of O.M.C.s and 1 samples of Pharmacy exceeded WHO's limit in fungi count. No samples exceeded WHO's limit in bacteria count. Most bacteria founded in samples were the phylum of Firmicutes and Proteobacteria which are common in soil by non-culture method. Conclusion : Further study should be followed to set up proper microbial limit of herbal materials including pill types.

Morphologic and Genetic Identification of Taenia Tapeworms in Tanzania and DNA Genotyping of Taenia solium

  • Eom, Kee-Seon S.;Chai, Jong-Yil;Yong, Tai-Soon;Min, Duk-Young;Rim, Han-Jong;Kihamia, Charles;Jeon, Hyeong-Kyu
    • Parasites, Hosts and Diseases
    • /
    • v.49 no.4
    • /
    • pp.399-403
    • /
    • 2011
  • Species identification of Taenia tapeworms was performed using morphologic observations and multiplex PCR and DNA sequencing of the mitochondrial cox1 gene. In 2008 and 2009, a total of 1,057 fecal samples were collected from residents of Kongwa district of Dodoma region, Tanzania, and examined microscopically for helminth eggs and proglottids. Of these, 4 Taenia egg positive cases were identified, and the eggs were subjected to DNA analysis. Several proglottids of Taenia solium were recovered from 1 of the 4 cases. This established that the species were T. solium (n=1) and T. saginata (n=3). One further T. solium specimen was found among 128 fecal samples collected from Mbulu district in Arusha, and this had an intact strobila with the scolex. Phylegenetic analysis of the mtDNA cox1 gene sequences of these 5 isolates showed that T. saginata was basal to the T. solium clade. The mitochondrial cox1 gene sequences of 3 of these Tanzanian isolates showed 99% similarity to T. saginata, and the other 2 isolates showed 100% similarity to T. solium. The present study has shown that Taenia tapeworms are endemic in Kongwa district of Tanzania, as well as in a Previously identified Mbulu district. Both T. solium isolates were found to have an "African/Latin American" genotype (cox1).