• The Plant Pathology Journal
• /
• 제28권4호
• /
• pp.423-427
• /
• 2012

Pseudomonas syringae pv. actinidiae strains, the causal agents of bacterial canker on kiwifruit, were isolated from Korea and Italy in 2011. Among 87 isolates, a total of six representative strains, three from Korea and three from Italy, were identified on the basis of biochemical and physiological tests. Identities were confirmed by PCR using P. syringae pv. actinidiae-specific primers PsaF1/R2, which amplified a 280-bp DNA fragment. The strains isolated from Korea in this study displayed BOX-PCR patterns similar to those isolated from Italy but different from those isolated previously in Korea or the pathotype P. syringae pv. actinidiae strain. The effector hopA1 and hopH1 genes, which are known to be present in strains isolated recently from France and Italy, were also present in P. syringae pv. actinidiae strains, SYS1, SYS2 and SYS4, isolated from Korea in this work. However, no amplicons of the expected size were obtained from strains previously isolated from Korea and Japan. In addition, the Korean strains isolated in this work belonged to haplotype I for the cts gene identical to those strains isolated from recent outbreaks in Italy. These results suggest that P. syringae pv. actinidiae strains isolated from Korea and examined in this work are a new type of strain similar to those found from recent outbreaks in Italy. This is the first report on the occurrence of cts haplotype I strains of P. syringae pv. actinidiae affecting kiwifruit plants in Korea.

• KSBB Journal
• /
• 제15권4호
• /
• pp.359-365
• /
• 2000

Three lactic acid bacteria (C-1 K-3 and T-1 strain) were isolated from Nuruk and characterized subsequently. They were useful strains for production of lactic acid and their growth was inhibited at 10% ethanol pH 4 These strains were identified as lactococcus lactis subsp. lactis NR C-1 Leuconostoc mesenteroides subsp. mesenterides NR K-3 and pediococcus pentosaceus NR T-1 respectively by morphological physiological and biochemical characterization Lac lactis subsp lactis NR C-1 showed the highest lactic acid productivity. Leu measenteroides subsp mesenteroides NR K-3 showed stable lactic acid productivity and its growth was inhibited at pH 4. P pentosaceus NR T-1 had lower lactic acid productivity than the other two bacteria but it could not grow at 10% ethanol pH 4 The lactic acid productivity of these three strains in MRS broth were higher than that in Skim milk media the optimum pH and temperature for the lactic acid production of the three strains were 30-32$^{\circ}C$ and pH 6.0∼6.8 Glucose was the optimal carbon souorce for the lactic acid production. In terms of antagonism lac lactis subsp lactis NR c-1 showed somewhat inhibitory efects against some Gram positive rod and cocci such as Lactobacillus brevis and Streptococcus mitis. And Leu mesenteroides subsp mesenteroides NR K-3 showed the inhibitory effects against Streptococcus mitis but P. pentosaceus NR T-1 didn't show any inhibitory effects against tested strains.

• 한국미생물·생명공학회지
• /
• 제37권1호
• /
• pp.10-16
• /
• 2009

생합성 유전자들이 알려져 있고 탐색할 후보 균주들이 확보되어있는 경우에 중합효소연쇄반응(PCR)은 유용한 이차 대사산물을 생산하는 새로운 균주의 탐색에 있어서 간편한 방법이 될 수 있다. 본 연구에서는 중합효소연쇄반응에 의해 50균주의 셀룰로오스 분해성 점액세균로부터 강력한 항진균물질 soraphen의 생합성 유전자로 보이는 유전자를 가지는 두 점액세균 균주 KYC3047과 KYC3076를 선별하였다. 그리고 형태학적, 생리학적, 분자생물학적 특성에 의해 이들 균주들을 S. cellulosum로 동정하였다. 두 균주는 모두 예상한대로 칸디다증을 유발하는 Candida albicans와 고추 탄저병을 유발하는 Colletotrichum acutatum에 강한 항균활성을 갖는 물질을 생산하였다.

• Journal of Microbiology and Biotechnology
• /
• 제13권1호
• /
• pp.110-118
• /
• 2003

Pseudomonas syringae pv. actinidiae strains, which cause canker disease in kiwifruit, were collected from kiwifruit orchards in Korea and identified using biochemical and physiological tests. The nucleotide sequences of the 16s rDNA and 16s-23s internally transcribed spacer of the isolates were found to be Identical to those of' the pathotype strain, Kwl 1, of P syringae pv. actinidiae. Remarkably, no coding sequence for phaseolotoxin biosynthesis or phaseolotoxin- resistant ornithine carbamoyltransferase was found by PCR amplification in any of the new Korean isolates of pseudomonas syringae pv. actinidiae, although this was clearly identified in the control pathotype Kwl 1 reference strain. In contrast, three primer sets derived from the coronatine biosynthetic gene cluster and DNA from the Korean strains yielded amplified DNA fragments of the expected size. A sequence analysis of the PCR products revealed that P. syringae pv. actinidiae and the Korean strains of pv. actinidiae contain coronafncate ligase genes (cfl)with identical sequences, whereas their. corR genes exhibited 91% sequence similarity. The production of coronatine, instead of phaseolotoxin, by the Korean strains of P. syringae pv. actinidiae was confirmed by a bioassay using reference pathovars known to produce coronatine and phaseolotoxin. The genes for coronatine biosynthesis in the Korean strains of P. syringae pv. actinidiae were found to be present on plasmids.

• Journal of Species Research
• /
• 제7권2호
• /
• pp.123-134
• /
• 2018

A total of 22 bacterial strains belonging to the phylum Bacteroidetes were isolated primarily from aquatic environments such as seawater, freshwater, lagoon and tidal flat. One of these 22 strains was isolated from ginseng soil. Phylogenetic analyses based on 16S rRNA gene sequences revealed that 21 strains showed the high sequence similarities(${\geq}98.7%$) to the closest type strains and formed robust phylogenetic clades with closely related species in the phylum Bacteroidetes. One strain, which had been previously classified as Balneola vulgaris in the phylum Bacteroidetes, was identified as a member of the newly described phylum Rhodothermaeota. These strains had not been previously reported in Korea. Here, we report 21 species of 13 genera in the phylum Bacteroidetes and one species in the phylum Rhodothermaeota which were not reported in Korea. Morphological, biochemical, and physiological characteristics, isolation sources, and NIBR deposit numbers are described in the species descriptions.

• 한국균학회지
• /
• 제21권2호
• /
• pp.127-132
• /
• 1993

269 yeast strains were isolated from water samples collected from different sites in Minia governorate. These included 126 strains from fresh water, 108 strains from sewage and 35 strains from wastewater from sugar-cane factory. On the basis of 23 different physiological and morphological merkmals, the isolated strains were assigned to 16 species belonging to 11 genera. Total yeast cell counts as well as spectra of yeast species were highly variable in tested water. Total yeast cell counts ranged between $3.0{\times}10^3/l\;and\;1.8{\times}10^6/l$ for fresh water, $3.0{\times}10^4/l\;and\;3.0{\times}10^7/l$ for sewage and $1.5{\times}10^6/l\;and\;2.6{\times}10^7/l$ for wastewater from sugarcane factory. Debaryomyces hansenii, Rhodotorula mucilaginosa and Torulaspora delbrueckii were the dominant species in fresh water, whereas Debaryomyces hansenii, Thrichosporon beigelii, Rhodoforula mucilaginosa and Kluyveromyces marxianus were the dominant species in sewage and Saccharomyces cerevisiae, Kluyveromyces marxianus and Trichosporon beigelii were the dominant species in wastewater from sugar-cane factory. Yeast human pathogens, Trichosporon beigelii, Rhodotorula mucilaginosa and Candida albicans were encountered in water samples indicating that water in El-Minia governorate is also polluted by some pathogenic yeasts.

• 한국균학회지
• /
• 제51권1호
• /
• pp.7-24
• /
• 2023

More than five hundreds of yeast species (including 9 variants) encompassing 142 genera and 48 classes of 2 phyla exist in Korea. However, only 173 species have been cataloged in the National Species List of Korea (NSLK), the backbone reference to claim sovereign rights over biological resources, as of December 2021, due to the lack of taxonomic descriptions, although some of these species are extensively used in industry. The present pilot study investigated the taxonomy of strains belonging to the six most widely used or frequently isolated yeast species (Meyeromyma guilliermondii, Saccharomyces cerevisiae, Saccharomycopsis fibuligera, Wickerhamomyces anomalus, Candida tropicalis, and Papiliotrema flavescens) to include these species in the NSLK. Strains with diverse habitats and geographic origins were retrieved from the National Institute of Biological Resources culture collection. These strains clustered in the same clade as the type strains of the designated species according to phylogenetic analysis of the D1/D2 sequences. Moreover, we described the cell morphology and physiological characteristics of representative strains of each species. This study suggests that these six species are indigenous to Korea and can be accordingly listed in the NSLK.

• Journal of Microbiology and Biotechnology
• /
• 제29권2호
• /
• pp.209-221
• /
• 2019

Gamma-aminobutyric acid (GABA) is a neurotransmitter that exerts several physiological functions and positive effects on human health. The aim of this study was to isolate and characterize the strains that had GABA-producing abilities from various fermented fish products. A total of 91 acid-producing strains were isolated from 41 samples of fermented fish products, and 27 strains showing GABA-producing abilities were identified by the 16S rDNA sequences. Among the strains, 31% strains tolerated at high-salt environment of 10-20% throughout the fermentation of fish sauces. The 27 isolates that produced GABA at various concentrations did so in the range of 5 to 454 mM. These GABA-producing isolates were identified as lactic acid bacteria of 14 strains, which included twelve Lactococcus lactis, one Enterococcus faecium, and one Lactococcus pentosus; eight Bacillus cereus group, which included seven B. thuringiensis and one B. cereus; and five Staphylococcus spp. Interestingly, with Vietnamese fish sauces, we mostly identified species of B. thuringiensis and Staphylococcus spp., while with Korean fermented fish products, the majority of the strains identified belonged to L. lactis. Among the strains, B. thuringiensis LH2134 produced the highest levels of GABA at 366 mM among the strains identified from Vietnamese fish sauces, whereas L. lactis LA43, a new strain isolated from Korean jeotgal (salted shrimp paste), produced the highest amount of GABA at 454 mM and the glutamate concentration in the medium was essential for GABA accumulation. Therefore, such the isolates might serve as good starters for development of more GABA-reinforced foods among fermented fish products.

• Current Research on Agriculture and Life Sciences
• /
• 제5권
• /
• pp.40-51
• /
• 1987

광교(光敎)를 비롯한 12개품종(個品種)의 대두근류(大豆根瘤)로부터 탐색분리(探索分離)한 질소고정균(窒素固定菌)의 생리적(生理的) 특성(特性) 및 숙주작물(宿主作物)과의 접종친화성(接種親和性)을 조사(調査)한 결과(結果)는 다음과 같다. 1. YMA배지(培地)에서 자란 질소고정균(窒素固定菌)의 색상(色相)은 백색상(白色相), 반투명색상(半透明色相), 투명색상(透明色相)이 각각(各各) 60%, 30%, 10%였으며 Litmus milk 반응(反應)은 alkali, acid serum, alkali serum, acid가 각각(各各) 51%, 29%, 9%, 11%로 나타났다. 2. 우량질소고정균(優良窒素固定菌)의 YM배지(培地)에서의 생육속도(生育速度) 및 pH의 변화(變化)는 S 022, S 096이 생육속도(生育速度)가 느리고, alkali를 생성(生成)하였으며 S 080, S 090, S 118은생육속도(生育速度)가 빠르고 산(酸)을 생성(生成)하였다. 3. YM배지(培地)의 초기(初期) pH가 6.0~7.0의 범위(範圍)에서 Rhizobia의 생육(生育)이 가장 좋았다. 4. 질소원(窒素源)으로서 glutamine, asparagine, allantion 등(等)은 Rhizobia의 생육(生育)을 촉진(促進)시켰다. 5. 분리(分離)한 균주(菌株) 전부(全部)가 대두(大豆)에 근류(根瘤)를 형성(形成)시켰으며, 우량질소고정균주(優良窒素固定菌株)는 그중 색상(色相)이 백색(白色)이고 colony가 소형(小型)이며 질산환원력(窒酸還元力)이 있고 아질산환원력(亞窒酸還元力)이 없으나 비교적(比較的) 높은 질소고정력(窒素固定力)을 나타냈다. 6. 동일균주(同一菌株)라도 숙주작물(宿主作物)의 친화성(親和性)에 따라서 질소고정능력(窒素固定能力)에 차이(差異)가 있었으며, 질소고정능력(窒素固定能力)이 없는 무효근류(無效根瘤)를 형성(形成)하는 균주(菌株)도 있었다.

• The Korean Journal of Ecology
• /
• 제12권2호
• /
• pp.75-82
• /
• 1989

Bacterial strains which have excellent removal capacity of phosphate or reduction capacity of were isolated from waste water. Among isolated strains. WR8 and WR1 strains were showed goood efficiency in removal of phosphate and reduction of respectively. When each strain was cultivated in waste water, WR8 strain removed about 85% of phosphate and WR1 strain reduced about 85% of -N. By the result of investigation of morphological and physiological characteristics, WR8 was identified as Aeromonas hydrophila and WR1 as Klebsiella pneumoniae.