• Title/Summary/Keyword: Strain specificity

Search Result 159, Processing Time 0.029 seconds

Value of Ultrasound Elastography in Assessment of Enlarged Cervical Lymph Nodes

  • Teng, Deng-Ke;Wang, Hui;Lin, Yuan-Qiang;Sui, Guo-Qing;Guo, Feng;Sun, Li-Na
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.5
    • /
    • pp.2081-2085
    • /
    • 2012
  • Background: To investigate the value of ultrasound elastography (UE) in the differentiation between benign and malignant enlarged cervical lymph nodes (LNs). Methods: B-mode ultrasound, power Doppler imaging and UE were examined to determine LN characteristics. Two kinds of methods, 4 scores of elastographic classification and a strain ratio (SR) were used to evaluate the ultrasound elastograms. Results: The cutoff point of SR had high utility in differential diagnosis of benign and malignant of cervical lymph nodes, with good sensitivity, specificity and accuracy. Conclusion: UE is an important aid in differential diagnosis of benign and malignant cervical LNs.

Production and Characterization of Extracellular $\beta$-Lactamase from Streptomyces aureofaciens SMF14

  • Kim, Myung-Kuk
    • Journal of Microbiology and Biotechnology
    • /
    • v.3 no.3
    • /
    • pp.174-180
    • /
    • 1993
  • A strain SMF14 producing an extracellular $\beta$-lactamase was isolated from soil and identified to be a strain of Streptomyces aureofaciens. $\beta$-Lactamase was purified from the cell free culture broth through batchwise hydroxyapatite adsorption, anion exchange chromatography on DEAE Sephadex A-50, gel filtration on Sephadex G-75, and adsorption chromatography on hydroxyapatite. The molecular mass was estimated to be about 43 kDa by SDS-PAGE. The $\beta$-lactamase had substrate specificity to penicillins and it was inhibited by clavulanic acid, being classified to the group 2a of penicillinase.. The optimal reaction pH and temperature were pH 6.0~7.5 and $50^{\circ}C$. The $K_m, and V_{max}$ values of $\beta$-lactamase for penicillin G were calculated to be 1.72 mM and 5.4$\times$$10^5 \mu M \cdot min^{-1}$, respectively.

  • PDF

Analysis of Mating System in Lentinula edodes and Development of Mating Type-Specific Markers

  • Ha, Byung-Suk;Kim, Sinil;Ro, Hyeon-Su
    • 한국균학회소식:학술대회논문집
    • /
    • 2014.10a
    • /
    • pp.42-42
    • /
    • 2014
  • Mating of tetrapolar mushrooms is regulated by to chromosomal loci, A and B. A locus contains A gene that expresses a homeodomain protein whereas B locus contains multiple pheromones and receptor genes. In order to characterize the mating loci in Korean cultivated strains of Lentinula edodes, one hundred monokaryotic myclelia were isolated from the basidiospores of cultivated strains, including Cham-A-Ram, Sanjo701, and Sanjo707. Both mating loci were amplified using primer sets targeting conserved sequence regions for homeodomain (HD), pheromone, and receptor genes. Subsequent sequence analysis revealed that the Korean strains contained significant variations in the homeodomain of A locus, even within the same A1 or A2 mating type. Similarly, B locus was also highly diversified in the sequences of pheromones and receptors as well as gene organization. These results enabled us to design mating type-specific probes which can distinguish mating type of each strain. The specificity was confirmed by between intra- and inter-strain mating experiment.

  • PDF

Studies on the Optimum Conditions of Soy Protein Coagulating Enzyme Production from Bacillus sp. IJ-3 Strain and the Action of IJ-3 Strain Enzyme on 75 Globulin (Bacillus sp. IJ-3가 생산하는 대두단백응고효소의 최적생산 조건 및 7S Globulin에 대한 효소적 작용에 관한 연구)

  • 박양원;김영전
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.25 no.5
    • /
    • pp.878-884
    • /
    • 1996
  • A bacterial strain, designated as Bacillu sp. IJ-3 strain, was shown to produce the extracellular soy protein coagulating enzyme and culture conditions for the production of enzyme by this microbial strain was investigated. The culture medium giving a maximum soy protein coagulating activity was consist of 20%(w/v) soymilk, 2.0%(w/v) glucose, 4.0%(w/v) yeast extract, 5.0%(w/v) polypeptone and 1.0%(w/v) potassium phosphate, monobasic. Initial pH was optimal at 6.0 and the enzyme activity in the culture usually reached a maximal level of fermentation at $35^{\circ}C.$ After the culture medium adjustment where required, enzyme activity was reached maximum at 72 hour of cultivation but this enzyme activity was reduced quickly. It can be assumed that Bacillu sp. IJ-3 strain enzyme has a specificity toward the 75 globulin.

  • PDF

Cellulase 및 hemicellulase의 고생산균주 FJ1의 효소생산 특성 연구

  • Kim, Gyeong-Cheol;Yu, Seung-Su;O, Yeong-A;Jeong, Seon-Yong;Kim, Seong-Jun
    • 한국생물공학회:학술대회논문집
    • /
    • 2001.11a
    • /
    • pp.629-632
    • /
    • 2001
  • The strain FJ1 isolated from a rotten wood showed high activity to hydrolysis of cellulosic materials. The strain produced largely enzymes related in hydrolysis of cellulose and hemicellulose, such as CMCase, xylanase, ${\beta}-glucosidase$ , and avicelase. The culture conditions(pH, temperature, inoculation concentration) and substrate specificity to various cellulosic materials were examined to elevate productivity of the enzymes. The enzyme activities of CMCase and xylanase were 13.5U/ml and 24.3U/ml in agitation culture using Mandel's medium, respectively. The high activity of the enzymes was earned when mixed cellulosic materials of rice straw, sawdust, and pulp as substrates, indicating that the strain FJ1 could use crystalline substrates.

  • PDF

Molecular Cloning and Functional Expression of esf Gene Encoding Enantioselective Lipase from Serratia marcescens ES-2 for Kinetic Resolution of Optically Active (S)-Flurbiprofen

  • Lee, Kwang-Woo;Bae, Hyun-Ae;Lee, Yong-Hyun
    • Journal of Microbiology and Biotechnology
    • /
    • v.17 no.1
    • /
    • pp.74-80
    • /
    • 2007
  • An enantioselective lipase gene (esf) for the kinetic resolution of optically active (S)-flurbiprofen was cloned from the new strain Serratia marcescens ES-2. The esf gene was composed of a 1,845-bp open reading frame encoding 614 amino acid residues with a calculated molecular mass of 64,978 Da. The lipase expressed in E. coli was purified by a three-step procedure, and it showed preferential substrate specificity toward the medium-chain-length fatty acids. The esf gene encoding the enantioselective lipase was reintroduced into the parent strain S. marcescens ES-2 for secretory overexpression. The transformant S. marcescens BESF secreted up to 217kU/ml of the enantioselective lipase, about 54-fold more than the parent strain, after supplementing 3.0% Triton X-207. The kinetic resolution of (S)-flurbiprofen was carried out even at an extremely high (R,S)-flurbiprofen ethyl ester [(R,S)-FEE] concentration of 500 mM, 130 kU of the S. marcescens ES-2 lipase per mmol of (R,S)-FEE, and 1,000 mM of succinyl ${\beta}-cyclodextrin$ as the dispenser at $37^{\circ}C$ for 12h, achieving the high enantiomeric excess and conversion yield of 98% and 48%, respectively.

Spontaneous Release of Bacteriophage Particles by Lactobacillus rhamnosus Pen

  • Jarocki, Piotr;Podlesny, Marcin;Pawelec, Jaroslaw;Malinowska, Agata;Kowalczyk, Sylwia;Targonski, Zdzislaw
    • Journal of Microbiology and Biotechnology
    • /
    • v.23 no.3
    • /
    • pp.357-363
    • /
    • 2013
  • The identification of bacteriophage proteins on the surface of Lactobacillus rhamnosus Pen was performed by LC-MS/MS analysis. Among the identified proteins, we found a phage-derived major tail protein, two major head proteins, a portal protein, and a host specificity protein. Electron microscopy of a cell surface extract revealed the presence of phage particles in the analyzed samples. The partial sequence of genes encoding the major tail protein for all tested L. rhamnosus strains was determined with specific primers designed in this study. Next, RT-PCR analysis allowed detection of the expression of the major tail protein gene in L. rhamnosus strain Pen at all stages of bacterial growth. The transcription of genes encoding the major tail protein was also proved for other L. rhamnosus strains used in this study. The present work demonstrates the spontanous release of prophage-encoded particles by a commercial probiotic L. rhamnosus strain, which did not significantly affect the bacterial growth of the analyzed strain.

Gene Cloning, Expression, and Characterization of Glucose-1-Phosphatase from Enterobacter cloacae B11

  • Kim, Young-Ok;Park, In-Suk;Nam, Bo-Hye;Kong, Hee-Jeong;Kim, Woo-Jin;Lee, Sang-Jun;Kim, Kyung-Kil
    • Fisheries and Aquatic Sciences
    • /
    • v.13 no.1
    • /
    • pp.49-55
    • /
    • 2010
  • A bacterial strain with phytase and glucose-1-phosphatase activity was isolated from seawater. The colony was identified as an Enterobacter cloacae strain and named E. cloacae B11. A gene, agpEnB11, coding for an intracellular acid glucose phosphatase was cloned from the strain and sequenced. It comprised 1,242 nucleotides and encoded a polypeptide of 413 amino acids. Recombinant glucose-1-phosphatase (AgpEn) was overexpressed in Escherichia coli and purified using Ni-NTA column under native conditions. Purified protein displayed a single band of 47 kDa on SDS-PAGE. AgpEn hydrolyzed a wide variety of phosphorylated compounds, with high activity for glucose-1-phosphate and glucose-6-phosphate. Optimum pH and temperature for enzyme activity were pH 5.0 and $50^{\circ}C$, respectively. Enzyme activity was stimulated by $Ca^{2+}$ and $Co^{2+}$, and inhibited by $Cu^{2+}$.

Investigation of Pathogenic Microbial Contamination in Medicinal Herb Products on the Market (유통 한약재에 대한 병원성미생물 분포)

  • Ham, Hee Jin;Yu, In Sil;Lee, Jib Ho;Kim, Su Jin;Yu, Young Ah;Lee, En Sun;Kim, Hee Sun
    • Korean Journal of Medicinal Crop Science
    • /
    • v.25 no.2
    • /
    • pp.108-114
    • /
    • 2017
  • Background: The study was conducted to investigate the distributions of faecal bacteria in commercial oriental medicine herb products. Methods and Results: A survey was conducted on the microbial contamination levels and antimicrobial specificity of Bacillus cereus and other microbes using 106 oriental medicine herb products on sale in Seoul. Pouring and isolation methods such as standard plate counts were used to identify the bacteria. The isolated bacterias included coliforms, Bacillus spp., Enterococcus spp., Staphylococcus spp., Listeria spp.were identified by using gram staining and an API (analytical profile index) kit. Antimicrobial drugs discs were determined by CLSI (clinical and laboratory standards institute). Conclusions: The bacterial isolates present in the herbal medicines included 98 coliforms, 45 Bacillus spp., 29 Enterococcus spp., and 2 Listeria spp. Among these, there were nine Bacillus cereus strains, one Enterococcus faecium strain, and one Enterococcus faecalis strain present. The 9 Bacillus cereus strains were tested for susceptibility to 36 types of antibiotics products by the disc diffusion method. The strains showed resistance to 13 of these antibiotic products and semi-resistance to 5 antibiotic products. On the basis of these results, any oriental medicine herb product can be assumed to be contain resistant or semi-resistant bacterial strains. Therefore, we suggest prescribing guidelines and special management for the use of antibiotics in farms producing oriental medicine herb products.