• Journal of Microbiology and Biotechnology
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• v.2 no.3
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• pp.166-173
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• 1992

The expression of Bacillus subtilis $\alpha$-amylase from the phoA-amyE fusion gene in recombinant E. coli was investigated under various environmental conditions. The overexpression of cloned $\alpha$-amylase caused retardations in cell growth and synthesis of alkaline phosphatase (AP) from the chromosomal phoA gene. The change of culture temperature from $37^\circ{C}$ to $30^\circ{C}$ increased the specific activities of both $\alpha$-amylase and $\beta$-lactamase by six and two times, respectively, whereas the AP activity remained unchanged. The experiments with chlorampenicol (a translation inhibitor) suggested the enhancement of $\alpha$-amylase activity at $30^\circ{C}$, and this was partly due to the stability of $\alpha$-amylase itself. The further decrease of the temperature to $25^\circ{C}$ slowed down both the cell growth and cloned-gene expression rate. The $\alpha$-amylase activity showed a maximum at pH of 7.4 while alkaline phosphatase was most effectively produced at pH of 8.3.

• The Korean Journal of Food And Nutrition
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• v.3 no.2
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• pp.149-160
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• 1990

The soybean $\beta$-amylase ($\alpha$-1, 4-glucan maltohydrolase, EC 3.2.1.2) is composed of seven isozymes(I', I, II, III, IV, V and VI), and isozyme II and IV are the main components among these. The Purification of $\beta$-amylase isozymes from soybean whey were performed by ammonium sulfate fractionation, CM-Sephadex C-50 column chromatography, DEAE-Sephadex chromatography and Gel filtration. The resulted purity of $\beta$-amylase was throughly confirmed by electrophoresis, and then determined its isoelectric point and molecular weight. The results obtained were as follows, 1. Five active fractions of soybean p-amylase were derived on CM-Sephadex C-50 column chromatography. 2. Seven active bands of p-amylase isozymes were detected by isoelectric focusing gel electrophoresis, and their isoelectric points(I' to VI) were 5.07, 5.15, 5.25, 5.40, 5.55, 5.70 and 5.93, respectively. 3. Isozyme II and IV were main components of soybean $\beta$-amylase. 4. The molecular weights of both isozyme II and IV were determined to be 56,000 daltons by the result of SDS polyacrylamide gel electrophoresis. 5. Km values of main isozyme II & IV for amylopectin were determined to be 2.25 mg/ml, which suggest the same function of each isozyme.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.529-533
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• 2001

The ${\beta}$-Amylase cDNA fragment from the oomcete Saprolegnia parasitica was cloned by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate oligonucleotide primers derived from conserved ${\beta}$-amylase sequences. The 5'and 3'regions of the $\beta$-amylase gene were amplified using the rapid amplification of cDNA ends (rACE) system. It consisted of an open reading frame of 1,350 bp for a protein of 450 amino acids. Comparison between the genomic and cDNA sequences revealed that the intron was not present in the coding region. The deduced amino acid sequence of the ${\beta}$-amylase gene had a 97% similarity to the ${\beta}$-amylase of Saprolegnia ferax, followed by 41% similarity to those of Arabidopsis thaliana, Hordeum vulgare, and Zea mays. The ${\beta}$-amylase gene was also expressed in Saccharomyces cerevisiae by placing it under the control of the alcohol dehydrogenase gene (ADC1) promoter.

• Journal of Plant Biology
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• v.11 no.1
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• pp.1-6
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• 1968

The effects of the different temperatures on the amylase activity and growth rate of the rye seedling grown in the solutions containing radioactive sulfur- 35 were studied. The amylase activity of the coleoptiles obtained from the seedlings grown in the solutions of S-35, at 14$^{\circ}C$, appeared to be strongly stimulated in comparison to the control, but the culture temperatures of 22$^{\circ}C$ and 3$0^{\circ}C$ showed the decrease in the amylase activity. The amylase activity of the grains treated with the low intensity of the ratioactive material didn't show clear changes, at any culture temperatures, but the amylase activity of the grains treated with the high intensity of S-35, 50$\mu$c, showed definite decline at the elevated culture temperature, 3$0^{\circ}C$. Similar effects was also found in the growth of the seedlings. However, we would consider the effects of the radioactive materials on the acticity of the amylase and the growth of the seedlings are resulted from the accumulation of the much amount of the radioactive materials, and this accumulation rate depends upon actually the elevation of the culture temperature.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.417-422
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• 1997

Recombinant Bacillus subtilis LKS88[pASA240] containing the amylase gene from Streptomyces albus KSM-35 was exploited in fed-batch cultivation for mass production of maltotetraose-producing amylase. The effects of dissolved oxygen, additional organic nutrients (peptone and yeast extract) and mixed carbon sources (glucose plus soluble starch) on amylase production were examined in fed-batch operations in an effort to determine the optimum conditions for a maximum amylase productivity. Under the optimum conditions, maximum amylase activity was about 4.2 times higher than that obtained in batch cultivations, indicating that mass production of maltotetraose-producing amylase could be accomplished in fed-batch cultivation of the recombinant B. subtilis strain.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.140-144
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• 2016

In this study, the physical factors for amylase production by Arthrobacter sp. were optimized using response surface methodology(RSM). Antarctic microorganism Arthrobacter sp. PAMC 27388 was obtained from the Polar and Alpine Microbial Collection(PAMC) at the Korea Polar Research Institute. This microorganism was confirmed for the excretion of amylase with Lugol's solution. The amylase activity was after flask culture was as low as 1.66 mU/L before optimization. The physical factors including the inoculum volume, the initial culture pH, and the medium volume were chosen to be optimized for the enhanced amylase production. The calculated results using RSM indicate that the optimal physical factors were 2.49 mL inoculum volume, 6.85 pH and 42.87 mL medium volume with a predicted amylase production of 2.84 mU/L. The experimentally obtained amylase activity was 2.50 mU/L, which was a 150% increase compared to the level before optimization.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.305-310
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• 1987

The enzymatic properties of ${\beta}-amylase$ from soybean and sweet potato were compared. The sweet potato enzyme consists of four identical subsunits whereas soybean enzyme has no subunit $structure^{12,\;15)}$. In the denatured state, both enzymes exhibited the same molecular weight on SDS-gel electrophoresis and on gel-filtration analysis. The spectra of circular dichroism revealed that both enzyme have almost same secondary structure but the environment of aromatic side chains are different. The chemical cleavage of soybean and sweet potato ${\beta}-amylases$ at cysteine residues and methionine residues demonstrated the homology of amino acid sequence between the enzymes. The similarity between soybean and sweet potato ${\beta}-amylase$ was also revealed by immunological method. The antibody for soybean enzyme inhibited the activity of sweet potato enzyme but it did not inhibit the activity of wheat, barley and Japanese-raddish ${\beta}-amylases$.

• Applied Biological Chemistry
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• v.31 no.4
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• pp.351-355
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• 1988

This study carried out to change ${\alpha}-amylase$ activity and isozymes in barley during germination in the dark and red light. The specific activity of ${\alpha}-amylase$ increased during the germination in the dark, giving 355.0 and 523.7 units/mg protein at 3 and 5 days, and the activity was increased by the red light up to 48 and 15% at 3 and 5 days of germination, respectively. The ratio of ${\alpha}-amylase$ I and II was approximately 95 : 5 at both 3 and 5 days of germination in the dark while the different ratio was found by the red light i.e. 60 : 40 and 90 : 10 at 3 and 5 days of germination, respectively.

• Microbiology and Biotechnology Letters
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• v.18 no.3
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• pp.309-316
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• 1990

The sequence of a 1795 bp restriction fragment containing the B. circulans F-2 gene for NaC1- dependent $\alpha$-amylase (CI-amylase) is reported. The probable coding region of the gene is 1005 base pairs (335 amino acida) long. The NaC1-dependent $\alpha$-amylase (el-amy) sequence shows an open reading frame (ORF) with the translated molecular weight of about 38, 006, which correspond to a molecular weight of about 35, 000 (Mi). The gene is preceded by the sequence resembling promoter for the vegetative B, subtitis RNA polymerases. These are followed by the sequences resembling a B. subtilis ribosome binding site 5 nucleotides before the first codon of the gene. Homologous regions with other amylases were found. The N-terminal sequences of the mature proteins expressed in E. eoli were identical to the N-terminal sequences which are anaIysed.

• Korean Journal of Food Science and Technology
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• v.1 no.1
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• pp.85-89
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• 1969

1. According to the Bergey's manual of determinative bacteriology, the high amylase producing strain A-162 isolated from corn was similar to Bacillus subtilis in the characteristics. 2. The addition of corn powder 30%, milk casein 5% and $CaCO_3$. 5% to wheat bran was excellent as amylase producing media. 3. According to vessel content and quantities of the media, the optimum steaming condition of media was different. Excessive steaming (pressure and time) suppressed the growth of Bacillus subtilis var. A-162. 4. The optimum temperature of amylase produced was about $50^{\circ}C$ and its optimum pH 6.0.