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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Microbiology and Biotechnology Letters
Journal Basic Information
Journal DOI :
The Korean Society for Applied Microbiology and Biotechnology
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Volume & Issues
Volume 16, Issue 6 - Dec 1988
Volume 16, Issue 5 - Oct 1988
Volume 16, Issue 4 - Aug 1988
Volume 16, Issue 3 - Jun 1988
Volume 16, Issue 2 - Apr 1988
Volume 16, Issue 1 - 00 1988
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Phytase-producing Microorganisms and Their Effects on the Fermentation of Soybean and Corn Meals -Isolation of Phytase-producing Microorganisms and Conditions for Enzyme Production-
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 433~473
Two isolates of C-7 and S-34, which were identified as Bacillus licheniformis and Enterobacter cloacae, were shown the highest phytase productivities among the 23 and 44 strains isolated from the fermenting corn and soybean meals, respectively. The phytase productivity with B. lichenifrmis was maximized at pH 6.0, 3
after 5 days of incubation and E. cloacae was maximized at pH 1.0, 35
after 5 days of incubation. The bacterial phytase productivity with each bacterium was significantly increased or decreased by the addition of various concentrations of 6 carbon and 7 nitrogen sources including glucose, sucrose, KNO
, and NH
Purification of the Convertible Enzyme of Ginseng Saponin from Rhizopus japonicus
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 438~442
The enzyme produced by Rhizopus japonicus was able to convert selectively ginsenoside-Rb
which is the most abundant ginseng saponin, into ginsenoside-Rd which was known to be superior to ginsenoside-Rb
pharmaceutically. The convertible enzyme was purified homogeneous from wheat bran culture of Rhizopus japonicus by ammonium sulfate fractionation and column chromatography of TEAE-cellulose, DEAE-Sephadex A-50, Sephadex G-150, Sepharose 2B. Specific activity of the purified enzyme was increased to a bent 96 folds and yield was appeared to be 11% of culture extract. Evidence for homogenity was obtained from polyacrylamide and SDS-polyacrylamide gel electrophoresis. Molecular weight of the enzyme was estimated about 88, 000 daltons by Sephadex G-l50 gel filtration and SDS-polyacrylamide gel electrophoresis, and it did not consist of any subunit.
Identification of Yeast Strains with Computer System
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 443~449
Three yeast strains isolated from various sources were tested in its morphological, physiological, and biochemical characteristics. The results were compared with those of 35 standard yeast strains in order to study important taxonomical characteristics for yeast identification and to find out the problem of computer identifying system. Although few characteristics did not coincide with literature data, three unidentified strains were temporarily identified as Saccharomyces exiguus, Candida edax, and Candida membranaefactence. The use of computer identifying system must be accomponied with conventional identification method because of the restriction of data sources for computer system.
Controlled Fed-Batch Cultivation of Escherichia coli Mutant for L-Tryptophan Production
Lee, In-Young ; Kim, Myung-Kuk ; Kho, Yung-Hee ; Kwak, Moo-Young ; Lee, Hosull ; Lee, Sun-Bok ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 450~456
For optimal production of L-tryptophan using a regulatory mutant of Escherichia coli the relationship between product formation and acid production was investigated. Experimental results showed that the production level of L-tryptophan was lowered as the specific acid production rate increased. In order to reduce the amount of acid produced during the fermentation, a controlled fed-batch fermentation was employed. In this fed-batch process, the feed rate of the nutrient feed medium was controlled in relation to the oxygen level in the culture and thus the growth of the cells was regulated in such n way that the oxygen demand of the culture could not exceed the oxygen sup-ply. When E. coli cells were cultivated in a controlled fed-batch mode of tormentor operation, the specific acid production rate was significantly reduced and L-tryptophan production was increased as much as five times that obtained in a conventional fed-batch fermentation.
Production of Raw Starch Digesting Enzyme by Streptomyces sp. 4M-2
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 457~462
A potent actinomycetes strain was selected to digest raw starch, which was classified as a strain of Streptomyces sp.. Its amylase production was maximized when it was grown on wheat bran extract media added 4% of cooked corn starch and 0.16% of potassium nitrate for 6 days at 3
and initial pH 6.2.
Characteristics and Occurance of Spontaneous Mutant in Lactobacillus casei YIT 9018
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 463~467
In this study characterization of spontaneous Lac
mutant of Lactobacillus casei YIT 9018 was investgated. The frequency of occuring the spontaneous Lac
mutant cells from stok culture strains was approximately 0.5% in MRS Media and 0.29% in 10% nonfat dried milk, ohterwise, that from pure Lac
colony it was 0.25% in MRS Media and 0.1% in l0% nonfat dried milk. In the physiological deference the spontaneous Lac
mutants were defective in lactose and/ or galactose-fermenting ability and also needed longer time for coagulation of nonfat dried milk than wild type.
Enzymatic Properties of Cytidine Deaminase Encoded by cdd Gene in Bacillus subtilis
Song, Bang-Ho ; Yoon, Mi-Sook ; Kim, Kyung-Hwa ; Yeo, Jeung-Sook ; Jan Neuhard ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 468~475
The cloned B. subtilis cdd gene encoding cytidine/2'deoxycytidine deaminase (EC 22.214.171.124) was expressed in the cdd deficient B. subtilis mutant ED40. The gene was isolted from the cdd complementing plasmid pSO21, and inserted into the EcoR1/Pvu1 sites of pGB215-110 ΔB, which is a temperature sensitivie E. coli-B. subtilis shuttle vector. In the transformed B. subtilis ED4O harboring the resulting plasmid pSO100, cdd was expressed at several hundred fold elevated levels, and the cytidine deaminase activity in E. coli containing pSO100 was twice the level in B. subtilis/pSO0100. The Km value for cytidine of the partially purified enzyme is 1.88
M at pH 7.0 and the V
mol/min/mg of protein. The enzyme was completely inhibited by 0.1M mercaptoethanol and HgCl
. The inhibition by p-chrolomercurybenzoic acid showed a Ki = 5 uM. These results suggest that sulfhydryl reagents block an active site thiol group, and/or disturb the formation of the tetrameic holoenzyme.
Construction of the Stable and High Copy Number Yeast Vectors
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 476~483
Yeat-Escherichia coli shuttle vectors were constructed by combination of various functional segments such as autonomous replicating sequence (ARS1), centromere region (CEN3), origin of replication of 2
m plasmid (2
m OR). Transformation efficiency, stability and copy number of constructed vectors were analyzed in yeast strains, SHY4(cir
) containing 2
m plasmid and NNY1(cir
) without it. The results showed that centromere containing plasmids were very stable and existed at one copy per cell; fused replication system (2
m OR and ARS1) containing Plasmids were more stable and higher copy number than one replicon containing plasmids ; presence of endogenous 2
m plasmid influenced on stability and copy number of 2
m based plasmids.
Characteristics of Extracellular Endo-Inulinase Produced by Pseudomonas sp.
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 484~488
Two forms of extracellular endo-inulinase, designated as PIand P II were resolved from a species of Pseudomonas isolated from soil. Both enzymes were glycoproteins with their carbohydrate content of 15% for PIand 2.4% for P II inulinase. Tryptophan residue was proved to be an essential amino acid for their catalytic activity. The molecular weights of PIand P II were estimated to be 210, 000 and 170, 000, respectively. The activity of the two enzymes was strongly inhibited by p-chloromercuribenzoate but the inhibition was nearly completely offset by the addition of the reducing agents such as cysteine or dithiothreitol. On the other hand, the two enzymes were activated about 50-60% of their activities by the presence of Co
ion, and quite stable at pH values ranging from pH 4.0 to 1.5. They also appeared to be relatively thermostable, and no appreciable inactivation was observed after incubation at 55
for 2 hours. About 70 % hydrolysis rate with PIand 56 % with P II were achieved when inulin was hydrolyzed at 5
for 12 hours with 60 units of the enzymes in 2 % inulin solution.
Heterologous Transformation of Saccharomyces cerevisiae by Glucoamylase Gene of Saccharomyces diastaticus
Kim, Young-Ho ; Jun, Do-Youn ; Seu, Jung-Hwn ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 489~493
To obtain a new yeast strain that is able to efficiently produce ethanol from starch, the glucoamylase gene of Saccharomyces diastaticus was transformed into S. cerevisiae without a cloning vector. The competent cells of S. cerevisiae, induced by the treatment of Li
, were transformed with the partial BamHI-digests of chromosomal DNA of S. diastaticus, and the transformants were selected by their abilities to utilize and ferment starch. The transformants, which appeared at a frequency of 8.5
, were able to withstand up to 800 ppm of copper sulfate like the recipient and retained the phenotypic expression of the recipient with the exception of the acquisition of STA gene and MAL gene, as regards fermentation of carbohydrates. The enzymatic properties of glucoamylases produced by transformants were very similar to those produced by S. diastaticus as based on optimium pH and temperature.
Culture Conditions for Glucoamylase Production and Ethanol Productivity of Heterologous Transformant of Saccharomyces cerevisiae by Glucoamylase Gene of Saccharomyces diastaticus
Kim, Young-Ho ; Jung-Hwn Seu ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 494~498
The optimum conditions for glucoamylase production, and ethanol productivity of the transformant TSD-14 were investigated as compared with the parental strains. The properties of TSD-14 were comparatively similar to the donor S. diastaticus IFO 1046 as regards the conditions of glucoamylase production and ethanol productivity. The soluble starch was the most effective carbon source for the glucoamylase production. While inorganic nitrogen sources did not prompt cell growth and enzyme production, the organic nitrogen sources generally enhanced both cell growth and glucoamylase production. The metal salts such as FeSO
, and NiSO
were favorable to the enzyme production. And the optium temperature and initial pH for glucoamylase production were 3
and 5. The transformant TSD-14 produced 8.3%(v/v) ethanol from 15% sucrose medium, 4.8%(v/v) ethanol from 15% soluble starch medium, and 7.5%(v/v) ethanol from 15% liquefied potato starch medium. The corresponding fermentation efficiency were 84% , 45% and 70%, respectively.
Isolation and Identification of Xylanase Secreting Yeast
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 499~504
Among the new yeast strains which were isolated from soils by incubating in the xylan containing minimal medium at 3
, one strain(XB-33) was finally selected by the results of extracellular xylanase production test. The characteristics of XB-33 was almost consistent with those of the Cryptococcus ater. The formation of xylanase activity was induced by xylan and repressed by xylose or glucose. The xylanase was partially purified from the culture supernatant with DEAE-Sephadex A5O chromatography. The enzyme had a pH optimum for activity at 5.0 and its stability range was pH 5-7. The temperature optimum was at 5
, but the enzyme activity was greatly lost by heating at 7
for 60 minutes. The hydrolysis products from xylan by crude enzyme detected by TLC, were xylose and n series of higher oligosaccharides. The Km value of xylanase was 20 (mg/ml).
Isolation and Identification of Xylose fermenting Yeast
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 505~509
Ethanol productivity of a xylose fermenting yeast (Candida sp. X-6-4l) isolated from soil was investigated in laboratory scale using Erlenmeyer flask and mini-jar tormentor. The optimal conditions of xylose fermentation in flask experiment were pH 4, asparagine as nitrogen source, xylose 20g/
, and in these condition, ethanol yield was about 80% to theoretical yield. Using mini-jar fermentor containing 5% total sugar with 2.5% xylose and 2.5% glucose, we obtained 2.3%(v/ v) ethanol and the corresponding efficiency was 72.3% of total sugar. In this case, the consumming speed of sugar under aerobic condition was faster than that of anaerobic condition, and glucose was used previously to xylose. The optimum concentration of xylose for ethanol fermentation in mini-jar fer-mentor scale was 5%, and the efficiency was 69% of total sugar(Alc.2.2% v/v).
Characteristics of the Bioreactors of Hydrogen-producing Immobilized Cells (II) -Overall Effectiveness Factor in Continuous Reactors-
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 510~516
The effects of input substrate concentration and dilution rate on mass transfer resistance in the operation of immobilized cell reactors were investigated using Rhodospirillum rubrum KS-301 immobilized by Ca alginate as reactor element and glucose as growth-limiting substrate. The kinetic parameters were obtained to estimate effectiveness factors. In the packed-bed reactor, internal mass transfer resistance was predominating although external resistance could not be neglected. The overall effectiveness factor was decreased with increase of dilution rate. In the continuous stirred-tank reactor, external resistance was nearly neglected and the overall effectiveness factor was not affected by dilution rate. In this experiment the overall effectiveness factors in PBR and CSTR were estimated to be 0.70 and 0.71 at D
= 0.2/h, R = 0.15 cm, and S
: 1.0g/L, respectively.
Assessment of Post-Pasteurization Contamination of Fluid Milk Products
Huh, Chung-Jae ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 517~521
This study focused on the psychrotrophic post-pasteurization contamination of fluid milk pro-ducts which were processed by HTST system. Pasteurized line samples and container samples of each fluid milk product (whole milk and skim milk) were taken in a large fluid milk plant. tine samples were collected through nine and five different sampling locations for whole milk and skim milk products, respectively. Each sample was subjected to preliminary incubation (PI) at 21
for 16h followed by standard plate count (SPC) and crystal violet tetrazolium agar count (CVT). Flavor, SPC, and psychrotrophic bacteria count (PBC) were determined after 7 d at 7.2
. In addition, ten sequential container samples (packaged in 1000ml paperboard containers) were taken from a filler at the beginning of each product run. These samples were used for PI followed by SPC and CVT. In addition, flavor evaluations, SPC and PBC tests were conducted after 7,10, and 14 d at 7.2
. The mean PI-CVT values for the line samples showed differences depending on the location. There was major contamination between pasteurized storage tank and the filler. The PI-CVT counts for each container sample were negatively correlated with flayer scores at 10 and 140. There were good correlations among PI-CVT values of line samples and the percentage of total container samples with acceptable flavor after 10d.
The Production of Tissue Type Plasminogen Activator from Normal Human Cell tine
Lee, Hyeon-Yong ; Kim, Geum-Soo ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 522~525
A method to produce tissue type Plasminogen Activator (tPA) from normal human fibroblast is developed by cultivating cells in serum free media containing heparin as an inducer. Optimal dose of this inducer was 30
. The composition of serum free medium was also defined to fit to the industrial scale cultivation. 1.42 ug of tPA per 10
viable cells per ml was produced. 1.1 gram of tPA can be produced every day from this cell line under normal perfusion chemostat operations assuming that same productivity is maintained when the process is sealed up. This method could reduce pro-duction costs and simplify purification processes by using serum free medium. Tissue type PA produced from this cell line has high ability of dissolving clots, based upon fibrin lysis test showing 50mm
of clearing zones in agarose gel plate. These results were reproducible and in good agreement with results of ELISA assay. tPA from normal human cells will be safer than that from melanoma and recombinant cells in human clinical trials.
Purification and Characterization of Proteases from Streptomyces sp. SMF301
Jeong, Byeong Chul ; Hyun Seung Shin ; Kye Joon Lee ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 526~531
Procedure for the purification of pretense from culture broth of Streptomyces sp. SMF301 was developed. It was evident that the strain produced two different proteases of which molecular weights were estimated to be 23, 500 and 38, 900 dalton. It was found that the optimum pH of the smaller was 9.0 and that of the larger was 1.0. The optimal temperature of the alkaline pretense was 5
and that of the neutral pretense was much more stable than neutral protease at extreme condition viz. high temperature, and pH.
The Biotechnological Application of Plant Cell Culture Engineering
Lee, Hyeon Yong ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 532~535
Chromosomal Mapping of the cdd Gene Encoding Deoxycytidine-cytidine Deaminase in Bacillus subtilis
Song, Bang-Ho ; Jan Neuhard ;
Microbiology and Biotechnology Letters, volume 16, issue 6, 1988, Pages 536~539
A mutant of Bacillus subtilis with a defective cdd gene encoding deoxycytidine-cytidine deaminase (EC 126.96.36.199) has been characterized genetically. The genetic lesion, cdd, causing the altered deoxycytidine-cytidine deaminase was mapped at 225 min on the linkage map of B. subtilis by AR9 transduction, Transductional analysis of the cdd region established the gene order in clockwise as trp-lys-cdd-aroD. The cdd gene was linked 72% with the aroD and 20% with the lys.