• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.364-369
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• 1999

In order to obtain the suitable plasmids for constructing plasmid vectors of Bacillus species, endogeneous plasmid DNAs were screended from thermo-tolerant soil bacteria. Based on agarose gel electrophoresis patterns of the isolated plasmid DNAs, two strains harboring small-size plasmids were selected. The isolated were identified to belong to the genus Bacillus on the basis of their morphological and biochemical properties, and named Bacillus sp. 3-3 and 77-8, respectively. The restriction endonuclease maps were determined for four plasmids including two plasmids from each Bacillus isolates. It is interesting that Bacillus sp. 3-3 and 77-8 have an identical plasmid according to the restriction maps. The three kinds of hybrid plasmids constructed by introducing each plasmid of two isolates into a Escherichia coli plasmid vector. pUCCm18 containing chloramplenicol resistance gene active in Bacillus strains, could be replicated in B. subtilis and B. licheniformis. These plasmids are very stable in B. subtilis, suggesting that the Bacillus plasmids identified in this work would be useful for development of new cloning vectors for Bacillus strains.

• Parasites, Hosts and Diseases
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• v.40 no.1
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• pp.25-31
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• 2002

We describe a riboprinting scheme for identification of unknown Acanthamoeba isolates at the species level. It involved the use of PCR-RFLP of small subunit ribosomal RNA gene (riboprint) of 24 reference strains by 4 kinds of restriction enzymes. Seven strains in morphological group I and III were identified at species level with their unique sizes of PCR product and riboprint type by Rsa 1. Unique RFCP of 17 strains in group II by Dde I. Taq I and Hae III were classified into: (1) four taxa that were identifiable at the species level. (2) a subgroup of 4 taxa and a pair of 2 taxi that were identical with each other. and (3) a species complex of 7 taxa assigned to A. castellanii complex that were closely related. These results were consistent with those obtained by 18s rDNA sequence analysis. This approach provides an alternative to the rDNA sequencing for rapid identification of a new clinical isolate or a large number of environmental isolates of Acanthamoeba.

• Journal of Advanced Marine Engineering and Technology
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• v.12 no.4
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• pp.32-45
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• 1988

The scanning moire method, in which the master grating is replaced by the scanning line of television camera and in which the moire pattern is obtained by thining out some scanning line, is discussed by the sampling theory. It is determined also by the sampling theory that relationship between the fringe pattern. The programs that analyze the strain by the scanning moire method have been developed. For the simulation model in which we are able to calculate analytically the distribution of strains, the scanning moire method is discussed. It is shown that the small strains and the large strains are analyzed from the same picture by the thinning out technique and that the accuracy of analysis is improved by change of the phase in the thinning out technique.

• The Journal of the Korean Society for Microbiology
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• v.11 no.1
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• pp.49-55
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• 1976

Two hundred and fourty eight strains of Pseudomonas aeruginosa isolated from clinical materials at Department of Bacteriology in National Medical Center and Han-il Hospital during January to November in 1973, were typed serologically by Hommo's agglutination method utlizing a routine set of 13 standard sera. In addition, their susceptibitily to several kinds of antibiotics were determind. The following results were obtained; One hundred seventy eight strains(71.77%) were typable with an occurence of type $T_8$ in 41 strains(16.53%), type $T_5$ in 36(14.52%), type $T_3$ in 24 strains(9.68%) and small numbers of strains were distributed in lither types. Seventy strains(28.23%) were nontypable. The rate of isolation of Pseudomonas by clinical meterials was shown as 49.19% in ous, 16.53% in sputum and 8.87% in urine; the isolation rate of 1.21-3.15% was shown in other clinical meterals and the definite distribution rate could not be observed in the serotype by different materials. Majorities of strains used in this experiment of isolates were resistant to common antibiotics but Gentamycin and Carbenicillin, known relatively as sensitive antibiotics to Pseudomonas aeruginosa, were observed resistance of 2.44-10.5% and 16.69-57.8%. Moreover any particular relationship between serotype and the sensitivity of antibiotics was not identified.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.37-37
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• 2018

Mating type of Lentinula edodes is determined by two unlinked genetic loci, A and B. To better understand mating behavior of L. edodes, we investigated variations in mating type genes in129 dikaryotic strains collected from East Asia. Through sequence analysis of A locus, we discovered that hypervariable region spanning N-term of HD2-intergenic region-N-term of HD1 could represent A mating type. Mating and hypervariable region analyses revealed 70 unique A mating types: 27 from 98 cultivated strains, 53 from 31 wild strains, and 10 commonly found. It was also revealed that only a few A mating type alleles such as A1, A4, A5, and A7 were prevalent in cultivated strains. Contrarily, A mating type in wild strains was highly diverse: 23 unique A alleles were discovered in small mountainous area in Korean peninsula, suggesting rapid evolution of A mating type in nature. The B locus was assessed by allelic variations in pheromone (PHB) and pheromone receptor (RCB) pairs which constituted subloci Ba and Bb. Sequence analyses and mating assay revealed 5 alleles of RCB1 with 9 associated PHBs in Ba sublocus and 3 alleles of RCB2 with 5 associated PHBs in Bb sublocus. Each RCB was primarily associated with two PHBs. Each PHB-RCB pair was always discovered as a distinct unit. This allowed us to propose 15 B mating types via combinations of five Ba and three Bb subloci. Further investigation on 129 strains confirmed that the B locus, unlike the A locus, was indeed restricted to 15 mating types. Thus, the total number of mating types became 1,050 in L. edodes through a combination of 70 A and 15 B. This number will further increase because of rapid diversification of A mating type. Our findings provide a comprehensive and practical knowledge on mating behaviors of L. edodes.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.141-147
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• 2008

Several contaminated bacteria such as Lactobacillus brevis and Pediococcus damnosus in beer production cause beer spoilage by producing off flavours and turbidity. Detection of these organisms is complicated by the strict anaerobic conditions and lengthy incubation times required for their cultivation, consequently there is a need for more rapid detection methods. Recently, two contaminated strains were isolated from vessel of beer production and identified as Lactobacillus species by API kit identificaton as well as 16S-23S ITS sequencing analyses. Two isolated strains were named as Lactobacillus sp. HLA1 and Lactobacillus HLB2, respectively. A polymerase chain reaction (PCR) method was developed for the rapid and specific detection of Lactobacillus sp.. Two sets of primer pairs (HLA1-F/HLA1-R and HLB2-F/HLB2-R) were designed for the amplification of a 1576 base pair (bp) fragment of the HLA1 16S-23S rRNA gene and 1888 bp fragement of the HLB2 16S-23S rRNA. Amplified PCR products were highly specific to detect corresponding bacteria when other contaminated strains were used as PCR templates. However, detection of both strains were limited when $100{\mu}{\ell}$ of cultured samples were mixed with $100m{\ell}$ of beer sample in arbitrary manner. The sensitivity of the assay still needs to be improved for direct detection of the small amounts of bacteria present in beer.

• The Korean Journal of Mycology
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• v.52 no.2
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• pp.145-153
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• 2024

While investigation of the fungal diseases on apples collected from Cheongsong-gun and Bonghwa-gun in Gyeongbuk province, Korea, between August and September 2023 isolated five fungal strains from fruits with sooty blotch and flyspeck (SBFS) disease. The strains were designated as KNUF-23-CS02, KNUF-23-CS-06, KNUF-23-CS12, KNUF-23-BH01, and KNUF-23-BH03. When grown on potato dextrose agar and 2% water agar, the cultural characteristics of the strains were similar to those previously reported characteristics of Peltaster fructicola Pf001. The strains produced monoblastic, hyaline conidiogenous cells; the conidia were hyaline, unicellular, cylindrical to ovoidal, and 3.5-7×1.7-3.9 and 4.0-6.6×1.8-3.2 μm in size on synthetic nutrient-poor agar or water agars, respectively. Secondary conidia production by microcyclic conidiation and budding was observed. The KNUF-23-BH03 strain was shown to cause SBFS symptoms similar to those observed on the apples in the pathogenicity test. Molecular phylogenetic analyses were conducted based on the isolated species sequences of the internal transcribed spacer region, nuclear large ribosomal DNA subunit, and mitochondrial small ribosomal RNA subunit gene. The five strains were clustered with Peltaster fructicola Pf001. Based on the cultural and morphological characteristics and phylogenetic analysis, the five strains were identified as Peltaster fructicola, which has not been previously reported in Korea.

• Parasites, Hosts and Diseases
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• v.34 no.2
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• pp.127-134
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• 1996

Twelve isolates of Accnthamoebc app. assigned to either A. castellanii or A. poIMphoSa, and type strains of A. culbefsoni, A. henIWi, A. pqkestinefiE, and A. astronyxi,s were examined by restriction fragment length polymorphism (RFLP) of a conserved region of small subunit ribosomal RMh gene (ssu rDNA) amplified by polymerase chain reaction (PCR). The PCR products of the isolates measured approximately 910-930 bp, except for that of A. astronyxis which was extraordinarily long, approximately 1,170 bp. Average of estimated sequence divergence of the amplified DNA among the isolates assigned to A. castellanii was 9.8% whereas that among the isolates assigned to A. polvphusn 9.6%. The maximum intraspecific sequence divergence among the isolates assigned to A. costellanii was observed between the Chang and Ma strains (17.3%) while that among the isolates assigned to A. poIWphosa was observed between KA/S3 and KA/S7 strains (16.1%). The both maximum sequence divergences were much greater than the minimum interspecific sequence divergence between A. cnstellnnii and A. polwphasa (2.6%) which appeared between the Castellani (or CCAP 1501/12 g) and KA/S3 strains. The PCR-RFLP patterns of A. culbertsoni, A. healyi, A. palestinensis, and A. ostronvxis were quite diverse from one another and from those of isolates assigned to either A. castellanii or A. polyphoga. It is suggested that taxonomic validity of the isolates assigned to either A. castellnnii or A. polyphoga should be reevaluated.

• Geotechnical Engineering
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• v.14 no.4
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• pp.33-46
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• 1998

Anisotropy of stiffness, from extremely small strains to post-failure strains, of isotropically consolidated air-pluviated sands in plane strain compression was studied by using the newly developed instrumentation for small strain measurements. Seven types of sand of the world-wide origins were tested, which have been extensively used for research purposes. Stress-strain at the specimen boundaries. It was found that the maximum Young's modulus $E_{max}$ was irrespective of the angle $\delta$ of the $\delta_1$ direction relative to the bedding plane. However, the normalized$ E_{max}$ was varied with the types of sand. Furthermore, the dependency of the strain and stress level on the stiffness was increased as $\delta$ decreased.

• Korean Journal of Veterinary Service
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• v.19 no.3
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• pp.213-219
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• 1996

Seventy-nine strains of Enterobacteriaceae isolated from 117 slaughtered pigs (bile, urine, small intestine, cecum and rectum) in 1995 were examined for biotypes and susceptibility to 19 antibiotics with MicroScan WalkAway 40/96. The obtained results were as follows : 1. Among the twenty-two species isolated from the samples, Proteus mirabilis, E. coli and Enterobacter cloacae were commonly encountered. 2. The distribution frequency of isolates from cecum, small intestine, rectum, bile, and urine was 31(38.8%), 25(31.3%), 18(22.8%), 3(3.7% ), and 2(2.5% ), respectively. 3. A majority of isolates were sensitive to 16 antibiotics, singly or in combination. And these isolates were commonly susceptible to various antibiotics such as Cp, Ts, Azt, Caz, To, Gm, Cfz, Crm, Am and Cfx, in order. Whereas the Salmonella spp was susceptible to Cf, Ti and Pi, and Proteus mirabilis to Imp, Tim, Cft and Cz. Meanwhile, no effect was found to Cf, Ak and Cax. 4. Among the antibiotic resistant strains, a total of 17 reistant patterns was noted End of these Ak Tim 45(57.0%), Ak Am Cf Cfx Cfz Tim 8(10.1%) and Ak Ti Tim 6(7.6% ) were frequently encountered.