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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 15, Issue 6 - Dec 1987
Volume 15, Issue 5 - Oct 1987
Volume 15, Issue 2 - Apr 1987
Volume 15, Issue 1 - Feb 1987
Volume 15, Issue 4 - 00 1987
Volume 15, Issue 3 - 00 1987
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Studies on the Fine Structure of Yeast -Fine Structure Alteration during Transformation-
Hong, Soon-Duck ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 1~1
The fine structure of transformed Saccharomyces cerevisiae DBY746 cells by YRp7 was observed in electronmicroscope comparing with normal cells, and optimal conditions for transformation were investigated. The most reasonable condition for the competent cell preparation was that the cells were introduced to 0.1M Li-acetate for one to two hours at
, because the Li-acetate was the most effective among various metals. The optimal temperature for heat shock was
, and polyethyleneglycol 4,000 was the most effective among various polythyleneglycol molecules used. The surface structure of transformed cells was very rough and somewhat shrinked compared to the native shape. Alkaline metal salts and surface active reagents were not effective to the change of fine structure of cells. The shrinked nucleus and swelled mitochondria were observed in the heat shocked cells under transmission electron imicroscope. Total numbers of mitochondria were increased and dispersed in the cytoplasm of the transformed cells.
Purification and Reaction Characteristics of Amplicillin Acylase from Pseudomonas melanogenum
Hur, Nam-Youn ; Oh, Doo-Hwan ; Yu, Ju-Hyun ; Nam, Doo-Hyun ; Kim, Jung-Hoe ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 9~9
The characteristics fo hydrolytic and synthetic reactions of ampicillin were studied with an ampicillin acylase obtained form Pseudomonas melanogenum IFO 12020 as forms of purified soluble enzyme and intact whole cell. An intracellular ampicillin acylase was purified from the sonicated culture broth by means of ammonium sulfate fractionation, sepharose-diaminohexyl-phenylacetic acid affinity chromatography, and sephadex G-200 gel filtration. The final preparation of the enzyme showed overall 294-fold purification with the final yield of 29.6% and the specific activity of 9.98 IU/mg-protein on ampicillin. The optimum pHs for hydrolytic and synthetic reactions were 5.5 and 6.0, respectively. The optimum temperatures for both reactions were
, respectively. The reaction conditions of intact whole cell enzyme and purified soluble enzyme were the same. Maximal conversions of ampicillin hydrolytic and synthetic reactions were 85% and 52%, respectively.
Isolation and Identification of Yeasts occurred in Inflated fluid Yogurts
Suh, Dong-Chul ; Hwang, In-Kyu ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 15~15
From 208 sweetende fluid yogurts, the fermenting yeasts causing inflation were isolated and identified through morphological, cultural ans physiological characteristics. A total of 31 yeast strains were isolated and indentified as belonging to the genera of Saccharomyces, Torulopsis and Kluyveromyces. Saccharomyces \cerevisiae was the most frequently isolated species, followed by Torulopsis candida, Torulopsis haemulonii, Saccharomyces fermentati, Kluyveromyces lactis, Saccharomyces montanus and Saccharomyces uvarum. The growth of yeasts in sweetened fluid yogurts was related to the abilities of the yeasts in sweetened yogurts to grow at refrigeration temperature, of ferment at least one of the sugars present in sweetened yogurts, such as sucrose and glucose with
production, to use the lactate as the energy source and to grow under low pH. About two thirds of the isolated yeast strains were identified as the genera of Saccharomyces or closely related species in sweetened fluid yogurts.
Development of Excellent Mutants for Manufacture of Ordinary Korean Soy Sauce and Soybean Paste
Ki, Woo-Kyung ; Kim, Jong-Kyu ; Kang, Dong-Hag ; Cho, Yong-Un ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 21~21
In order to manufacture ordinary Korean soy sauce and soybean paste rapidly and hygienically, several mutants were selected after N-methyl-N'-mitro-N-nitrosoguanidine(NTG) treatment from two Bacillus strains; the strain
isolated from soy sauce and
from soybean paste. As a result, the activity of
-amylase showed the highest value after 5-8 days by the inoculation in medium containing 10% soybean extract and the activity of protease was produced to maxium after 10-15 days. One of the mutants from
, produced strong ordinary Korean soy sauce flavor after 5 days in a medium containing 10% soybean extract. The original strains,
, and their mutants selected were well grown in a mineral medium containing 7% NaCl by addition of various amino acids, but the nutrient requirement of each strains was different. The growth of each strains was gradually was gradually inhibited by increasing NaCl concentration up to 8.7%. The strains produced highly protease and
-amylase in culture broth containing 5.8% NaCl, but the activities of their enzymes were not influenced nearly by NaCl concentration.
Molecular Cloning of CMCase Gene from an Alkalophilic Bacillus sp. in escherichia coli
Yu, Ju-Hyun ; Kong, In-Soo ; Kim, Sung-Uk ; Kim, Jin-Man ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 29~29
A new cellulase gene from Bacillus sp. strain N-4 has been cloned in Escherichia coli with pBR 322. A new plasmid named pYBC 107 was isolated from the E. coli transformants that produced carboxymethyl cellulase (CMCase). The cloned gene was contained within a 5.5kb Hind III DNA fragment of the chromosomal DNA part of the plasmid pYBC 107. The CMCase produced by E. coli(pYBC 107) located mainly (60%) within the cell wall and showed optimum activity and stability at pH 8.0.
Effect of Growth Rate on the Tylosin Biosynthesis in Streptomyces fradiae
Lee, Jeong-Hyun ; Lee, Kye-Joon ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 34~34
Batch and fed-batch fermentations of tylosin were carried out using Streptomyces fradiae in a synthetic medium. It was found that the trophophase-idiophase dynamics was not identified in a batch culture and that sodium glutamate and glucose were simultaneously metabolized with favor for glutamate. The rise of culture pH was resulted from the formation of ammonium ions after sodium glutamate utilization. Using fed-batch cultures it was found also that the optimal dilution rate for the tylosin biosynthesis was about
and the maximal specific tylosin formation rate(
) was calculated as 1.0mg/g/h.
Mutagenicity Tests of Human Interferon-
produced by Recombinant Escherichia coli
Cho, Nam-Jin ; Jung, In-Whoan ; Jung, Jae-Kyung ; Bok, Hae-Suk ; Kim, Je-Hak ; Kim, Hyun-Su ; Yoo, Moo-Yung ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 39~39
주사제의 변이원성에 관한 연구Human interferon-
)produced by redombinant Escherichia coli was studied for mutagenicity using the Ames method and in vivo cytogenotics. Hu rIFN-
had no mutagenic effect on S. typhimurium(TA1535, TA1537, TA1538, TA98 and TA100) at concentrations of 30, 3000 or 300000IU/plate. In the cytogenetic study, Hu rIFN-
had no clastogenic effect on rat's bone marrow cells at concentrations of
IU. These results suggest that Hu rIFN-
has no mutagenic potential.
Characteristics of Lipases in Two Phase System
Gwon, Dae-Yeong ; Kim, Gi-Hyeok ; Lee, Jun-Sik ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 43~43
Characteristics of Lipases from Candida rugosa and Rhizopus arrhizus during the hydrolysis of olive oil in two phase system were in vestigated for fat splitting and interesterification. Isooctane was used as an organic solvent for both lipases. The lipid hydrolysis rate of live oil by lipases in two phase system increased in proportion with the olive oil concentration up to 90%(v/v), whereas in emulsion system the rate increased only up to 5% of olive oil concentration and then decreased substantially thereafter with the increase of the substrate concentration. The lipid hydrolysis rate for various pH of the aqueous phase(containing lipases) in two phase system was maximum at pH 6.0 and 6.5 for the lipase from C. rugosa and R. arrhizus, respectively. The optimum temperature for the reaction was
for the Candida and Rhizopus lipases, repectively.
Citric Acid Production by Saccharomycopsis lipolytica in a Dual Hollow-fiber Bioreactor
Chung, Bong-Hyun ; Cho, Dae-Chul ; Chang, Ho-Nam ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 49~49
Continuous production of citric acid by Saccharomycopsis lipolytica was carried out in a dual hollow fiber bioreactor (DHFBR) designed for aerobic cell culture. In citric acid fermentation pH control was very important and thus buffered media were used during the DHFBR operation. Among the buffers used in the reactor operation,
-NaOH and phosphate buffers were more productive than NaOH-phthalate buffer. Volumetric productivity of the DHFBR using pure oxygen was 4.6g/l.h, which was superior to those of the DHFBR using air(2.55g/l.h) and the shake-flask(0.14g/l.h). Yield for citric acid in the shake-flask fermentation was 50%, which was 5% higher than that in the DHFBR using pure oxygen. Since the buffered media used in the DHFBR operation appeared not suitable in the citric acid fermentation, a new process for controlling pH in the reactor was proposed.
Coimmobilization of Zumomonas mobilis and Amyloglucosidase in x-Carrageenan for Simultaneous Saccharification and Ethanol Fermentation
Kim, Chul-Ho ; Lee, Gyun-Min ; Han, Moon-Hi ; Rhee, Sang-Ki ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 55~55
-Carrageenan for Simultaneous Saccharification and Ethanol FermentationCoimmobilization of Zymomonas mobilis cells and an enzyme, amyloglucosidase(AMG), in
-carrageenan was studied in order to perform simultaneous saccharification and ethanol fermentation(SSF) of sago starch. The coimmobilized cells and AMG successfully converted sagostarch(10-25%) into ethanol. Ethanol yields obtained in this range of strach concentration were 93-97% of the theoretical yield. It was also found that the coimmobilized system showed higher ethanol producing activity thant the free enzyme-free cells and the separately immobilized system. In continuous-flow fermentation using the coimmobilized Z. mobilis cells and AMG, the maximum ethanol productivity was 10.6g/l,h, with 53% of theoretical yield at D=0.4
A Study on Optimal Conditions for Protoplast Formation and Regeneration of Streptomyces cattleya
Song, Eun-Kyung ; Park, Young-Hoon ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 61~61
Optimal conditions for protoplast formation and regeneration of Streptomyces cattleya were investigated. YEME medium supplemented with 0.2%(w/v) of glycine and 35%(w/v) of sucrose was found to be more efficient for protoplast formation that the medium S which has conventionally been used for protoplast formation of other Streptomyces species. Porotoplast formation and regeneration could most efficiently by carried out with the mycelia harvested at late exponential and the transitional period to stationary growth phase, respectively. For efficientregeneration, a hypertonic medium(R1) containing high levels of sucrose concentration was required due to a high reversion rate of the cells. Regeneration efficiency was observed to increase upto 500 fold at 0.6-0.8M of sucrose concentration, compared to 0.3M inthe original okanish's medium. Other conditions such as metal ion requirement, temperature effect on the regeneration were also studied.
Optimization of Culture Media on CPC Production by Cephalosporium acremonium
Lee, Kyung-Ae ; Suh, Won-Chul ; Lee, Jung-Jun ; Min, Tae-Ick ;
Microbiology and Biotechnology Letters, volume 15, issue 1, 1987, Pages 68~68
A high cephalosporin C producing mutant strain C. acremonium
was obtained by treating the strain Cephalosporium acremonium
with mutagen(NTG). This strain
gave two fold increases of CPC production than the parent strain, C. acremonium
. The optimal complex medium for the CPC production was formulated as follows: sucrose 10%, soybean meal 6.0%, D. L-methionine 1.0%, calcium carbonate 0.2%. It was observed that the final CPC concentration at the end of the batch culture in round bottom flasks was 10g/l.