• Microbiology and Biotechnology Letters
• /
• v.22 no.6
• /
• pp.593-598
• /
• 1994

A bacterium KL-57 which exhibited biosurfactant activity was isolated. This bacterium was identified as Bacillus subtilis. The biosurfactant-producing gene of B. subtilis KL-57 was cloned into R subtilis MI113 by using plasmid pTB523. The plasmid DNA from the clone was found to carry a 18 kb PstI insert. The biosurfactant-producing gene was cleaved into 4 fragments by SmaI, 3 fragments by PvulI or EcoRl, 4 fragments by PvulI and EcoRI double digestion, 5 fragments by AccI, and 2 fragments by KpnI, HindIII or BamHI. By subcloning the 18 kb Pstl insert, a 2.3 kb EcoRl fragment conferred the biosurfactant producing activity on B. subtilis cells. The 2.3 kb had one HindIII cleave site. But Two fragments, which corresponds HindIII/EcoRl termini, exhibited no biosurfactant activity.

• Restorative Dentistry and Endodontics
• /
• v.20 no.2
• /
• pp.577-609
• /
• 1995

Bacteria have been regarded as one of the most important factors in pulpal and periapical diseases. Streptococci are frequently isolated facultative anaerobes in infected root canals. Recently molecular biological techniques have been rapidly progressed. This study was designed to apply the molecular biological tools to the identification and classification of streptococci in the endodontic microbiology. Streptococci isolated from infected root canals were identified with both Vitek Systems and API 20 STREP. Identification results were somewhat different in several strains of streptococci. Eighteen streptococci and enterococcal was difficult so to digest plasmid DNA using Hind III and EcoRI to differentiate strains by restriction enzyme analysis of plasmid DNA. 16S rDNA of chromosome was amplified by polymerase chain reaction(PCR) and then restricition fragment length polymorphism(RFLP) using several restriction enzymes was observed. The molecular mass of 16S rDNA of chromosomal DNA was approximately 1.4kb. There were three to five RFLP patterns using eight restriction enzymes. RFLP patterns digested with CfoI which recognizes four base sequences were identical in all stains. Hind III which recognizes six base sequences could not digest the 16S rDNA. Restriction enzymes which recognize five base sequences were suitable for RFLP pattern analysis. At least three different restriction enzymes were needed to compare each strains. 16S rDNA PCR-RFLP was simple and rapid to differentiate and classify strains and could be used in the epidemiological study of root canal infections.

• Korean Journal of Microbiology
• /
• v.32 no.4
• /
• pp.271-279
• /
• 1994

To develop a yeast strain which stably secretes both $\alpha$-amylase and glucoamylase and therefore is able to convert starch directly to ethanol, a mouse salivary $\alpha$-amylase cDNA gene with a yeast alcohol dehydrogenase I promoter has been introduced into the cell of a Saccharomyces diactaticus hybrid strain secreting only glucoamylase. To secrete both enzymes more stably without loss of the $\alpha$-amylase gene during a cell-multiplication, an integrating plasmid vector containing $\alpha$-amylase gene was constructed and introduced into the yeast cell. The results showed that the linearized form of the integrating vector was superior in the transformation efficiency and the rate of the expression of the $\alpha$-amylase gene than the circular type of the vector. The yeast transformant having a linearized plasmid vector exhibited higher mitotic stability than the yeast transformant habouring episomat plasmid vector. The transformant containing the linearized vector producing both $\alpha$-amylase and glucoamylase exhibited 2-3 times more amylolytic activity than the original untransformed strain secreting only glucoamylase.

• Korean Journal of Veterinary Service
• /
• v.32 no.1
• /
• pp.61-76
• /
• 2009

At the present study, it was aimed to explore the molecular genetic characterization of multiple antimicrobial resistant Salmonella spp. isolates from pigs and cattle. A total of 138 Salmonella Typhimurium (S. Typhimurium) isolates were typed with phage, among them, 83.3% of S. Typhimurium tested could divide into a 10 phage types. Definitive type 193 (DT193) (25.4%) and DT195 (24.6%) were exhibited as the dominant types. DT104 and U302 were found from pigs and cattle. On the other hand, S. Enteritidis had 6 phage types, of them, phage type 21 (PT21) and PT11b were the popular types. In the plasmid profiles, 135 of S. Typhimurium isolates were exhibited 1 to 6 plasmid bands which molecular weight ranged from 90 to 2kb. 35 isolates (25.4%) harbored a 90kb plasmid which is thought to be the serotype specific virulence plasmid. Two of twenty five S. Enteritidis had common plasmids at 2 and 1.5kb. With multiplex polymerase chain reaction, virulence genes (invA and spvC) were detected from all Salmonella spp. from 167 of S. Typhimurium, S. Enteritidis and chloramphenicol resistant S. Schwarzengrund, but some drug resistant genes, such as PSE-1, cml/tetR and flo were not determined but other drug resistant genes, for example TEM and int were found. The detection rates of spvC, TEM and int gene was 35.3%, 29.3% and 72.5%, respectively. The TEM gene was highly popular in S. Typhimurium, which was detected from ampicillin and amoxicillin resistant strains as 95.9%. int gene was able to detect from all the isolates identified as multidrug resistsnt (MDR), particularly DT193 was thought as the most prevalent virulence and multidrug resistance isolate. The major plasmid profile and drug resistance pattern of DT193 were 90, 40, 10.5, 6.3, 3.0kb and ACCbDNaPSSuT, respectively. MDR was commonly found in other phage types, particularly DT104, U302 and DT203.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.771-774
• /
• 2001

NADPH has been known as a regulating factor the biosynthesis of polyhydroxyalkanote(PHA), and the flux of NADPH for PHA biosynthesis could be enforced by the amplification of zwf gene encoding glucose 6-phosphate dehydrogenase. The recombinant plasmid pCZWF harboring PHA synthase, phbC from R. eutropha and zwf from E. coli were constructed, and were transformed to R. eutropha by electroporation. The biosynthesis of P(3HB-3HV) copolymer were carried out in transformant R. eutropha through the two-stage cultivation method using valerate as a precursor. The biosynthesis rate and PHA content of transformant R. eutropha harboring pCZWF were increased compared with transformant R. eutropha harboring only phbC. Especially, the molar fraction of 3HV was increased from 68% to 74% due to amplification of zwf gene. And the biosynthesis P(3HB-3HV) and P(3HB-4HB) carried out using propionate and ${\gamma}-butyrolactone$ as a precursor, respectively. But the rate, content, and molar fraction of biosynthesis copolymers were not influenced appreciably. This may be due to the reduced availability of NADPH.

• Korean Journal of Medicinal Crop Science
• /
• v.17 no.1
• /
• pp.26-32
• /
• 2009

The region containing 18S rRNA gene, ITS 1 and part of the 5.8S rRNA gene of the Atractylodes japonica Koidz was amplified by PCR and the product cloned in a pBluescript SK II plasmid. DNA sequence of the cloned DNA was determined and submitted to the GenBank (accession number EU678363). Phylogenetic analysis of the ITS 1 DNA showed close similarity with the other plant species of the family Compositae. The extract of the plant materials of five different members of the family Compositae was analyzed by HPLC to detect atractylon. Extract of the A. japonica Koidz showed presence of significant amount of atractylon. However, noticeable amount of atractylon was not detected by the same analyses from the extracts of the other plants belonging to the family Compositae including Artemisia capillaris, Chrysantemum zawadskii, Eclipta prostrata or Taraxacum platycarpum.

• Research in Plant Disease
• /
• v.29 no.1
• /
• pp.39-44
• /
• 2023

To diagnose lily fasciation, lily bulbs showing fasciation were collected from several greenhouses in Jeju Island, South Korea. Bacteria were isolated from the lily bulbs and amplified with both primers for fasA in plasmid and for putative glycosyltransferase epsH gene in chromosome of Rhodococcus fascians. Three bacterial isolates were detected with the P450 primer set and identified as R. fascians by NCBI blast analysis. Twelve bacterial isolates were identified as R. fascians using RS02785 primer set, including the three bacterial isolates identified as the same pathogen using the P450 primer set. Pathogenicity of these bacterial strains identified as R. fascians was demonstrated. Apparent symptoms were observed on wounded lily leaves after inoculation with each bacterial suspension whereas no symptom was found on lily leaves treated with H₂O. Furthermore, bacteria re-isolated from wounded sites were identified as R. fascians. Based on the results, these two sets of primers are recommended for quarantine of R. fascians.

• Journal of Microbiology and Biotechnology
• /
• v.14 no.5
• /
• pp.1089-1092
• /
• 2004

An actinorhodin nonproducing Streptomyces lividans was converted to an actinorhodin overproducer through a single chromosomal integration of an antibiotic regulatory gene, afsR2. This strain exhibited early actinorhodin production and an average of 37.5% higher productivity than the S. lividans containing multiple copies of afsR2 plasmid in a glucose-containing liquid culture.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.6
• /
• pp.985-992
• /
• 2007

The diversity of archaeal strains from six hypersaline environments in Turkey was analyzed by comparing their phenotypic characteristics and 16S rDNA sequences. Thirty-three isolates were characterized in terms of their phenotypic properties including morphological and biochemical characteristics, susceptibility to different antibiotics, and total lipid and plasmid contents, and finally compared by 16S rDNA gene sequences. The results showed that all isolates belong to the family Halobacteriaceae. Phylogenetic analyses using approximately 1,388 bp comparisions of 16S rDNA sequences demonstrated that all isolates clustered closely to species belonging to 9 genera, namely Halorubrum (8 isolates), Natrinema (5 isolates), Haloarcula (4 isolates), Natronococcus (4 isolates), Natrialba (4 isolates), Haloferax (3 isolates), Haloterrigena (3 isolates), Halalkalicoccus (1 isolate), and Halomicrobium (1 isolate). The results revealed a high diversity among the isolated halophilic strains and indicated that some of these strains constitute new taxa of extremely halophilic archaea.

• Journal of Microbiology
• /
• v.34 no.1
• /
• pp.38-39
• /
• 1996

The internal regions of nuclear small subunit rRNA from 6 plaeurotus species and 5 Pleurotus ostreatus strains were amplified by PCR and sequenced. The DNA sequences of 8 Pleurotus strains (P. ostreatus NFFA2, NFFA4501, NFFA4001, KFFA4001, KFCC11635, P florida, P. florida, P. sajor-cuju, P. pulmonarius, and P. spodoleucus) were idential, but P. cornucopiae differed from them in two bases out of 605 bases. However, p[hylogenetic analysis of the sequences by DNA-distance matrix and UPGMA methods showed that P. ostreatus NFFA2m1 and NFFA2m2, known as mutants of P. ostreatus NFFA2, belonged to anther group of Basidiomycotina, which is close to the genus Auricularia. The difference of the SSU rDNA sequences of P. cornucopiae from other Pleurotus species tested corresponds to the difference of mitochondrial plasmid type present in Pleurotus species as observed by Kim et al. (1993, Korean J. Microbiol. 31, 141-147).