• Journal of Microbiology and Biotechnology
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• v.16 no.8
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• pp.1185-1191
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• 2006

The expression of a pullulanase gene in Pichia pastoris was investigated. The gene encoding pullulanase was cloned by PCR using the chromosomal DNA of Bacillus naganoensis as the template. The expression vector pPIC9K-Pu was constructed by inserting the pullulanase gene into plasmid pPIC9K and then transformed into Pichia pastoris SMD 1168 by electroporation. Activity determination, SDS-PAGE, and PCR amplification indicated that the gene of the pullulanase from B. naganoensis had successfully been expressed in SMD 1168 and the molecular size of the expressed recombinant product was about 119.9 kDa. This is the first report on the successful expression of the pullulanase from B. naganoensis in P. pastoris. The transformant secreted recombinant pullulanase with the activity of 350.8 IU/ml in shake-flask culture. The properties of the recombinant pullulanase were characterized.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.669-671
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• 2000

Antimicrobial cationic peptides have attracted increasing research and clinical interest as a natural antibiotics due to their broad spectrum of antimicrobial activites and the rapid development of multidrug-resistant pathogenic microorganisms. In this study, first, we synthesized artificial fusion partner and cationic peptide genes (lactoferricin, magainin, protegrin-1, and indolicidin). Second, we constructed recombinant expression vectors and then transformed Pichia pastoris. Finally, expressed cationic peptides were purified and tested for their antimicrobial activites. Antimicrobial activity has been tested upon the appearance of clearing zone on the plate with the lawn of gram negative E.coli XL- I blue and garm positive Staphylococcus aureus. Protegrin-1 and Indolicidin have apparant activity of cationic peotides. This fusion technique may lead to a general and suitable tool for production of pure antimicrobial cationic peptides in Pichia pastoris.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.844-850
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• 1997

$\alpha$-Galactosidase was partially purified from the culture filtrate of pichia guilliermondii by Mannobiose-Sepharose affinity column chromatography. The galactosidase exhibited maximum activity at pH 4.5 and 4$0^{\circ}C$, and was stable in the pH and temperature ranges of 4 to 5.5 and 30 to 6$0^{\circ}C$, respectively. The enzyme was inhibited by $Hg^{2+}$ and $Ag^{2+}$. The enzyme activity was ot affected considerably by treatment with other metal compounds. The enzyme hydrolyzed melibiose to galactose and glucose, raffinose to galactose and sucrose, and $Gal^{3}Man_{3}(6^{3}-$\alpha$-galactosyl-1,4-mannotriose)$ to galactose and mannotriose. On the contrary, it could not hydrolyze $Gal^{3}Man_{4}(6^{3}-galactosyl-1,4-$\alpha$-mannotetraose)$.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.157-160
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• 2002

Probiotics can form profitab1e microorganisms in human or animal internal organs. When it is fed at domastic animals, can bring the rise of weight and prevention of disease. Pichia anonwla by new probiotics have antibiotic effect and oder reducing effect. we researched about optimal condition of pilot scale fermentation and freezed dry of pichia anonwla.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.68-73
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• 2004

Ferritin is an iron storage protein found in most living organisms. For expression and industrial use, human light chain ferritin (L-ferritin) was cloned from human liver cDNA library and expressed in Pichia pastoris strain GS115. The recombinant L-ferritin in Pichia pastoris was glycosylated. In a fed-batch culture, the cell mass reached about 57 g/l of dry cell weight, and the L-ferritin in the cell was increased to about 95 mg/l after 150 h. In an atomic absorption spectrometry analysis, the intracellular content of iron in the L-ferritin transformant was measured as $1,694{\pm}85\;\mu\textrm{g}g/g$, which is 5.4-fold more than that of the control strain. This L-ferritin transformant could serve as iron-fortified nutrients in animal feed stock.

• KSBB Journal
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• v.14 no.4
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• pp.482-489
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• 1999

As host for the production of eucaryotic heterologous proteins, methylotrophic yeast Pichia pastoris and Hansenula polymorpha are the most highly developed of a small group of alternative yeast species chosen for their perceived advantages. This paper describes the method to enhance the recombinant protein productivity with P. pastoris and H. Plymorpha. In these experiments, the effects of methanol induction timing, induction method, pH, culture temperature and kinds of nitrogen sources on foreign protein production were tested with P. pastoris and compared with H. polymorpha.. In addition, optimum methanol concentration as inducer and the effects of carbon sources on AOX1 or MOX promoter repression and secretion efficiency were also studied in both cases.

• Journal of Applied Biological Chemistry
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• v.50 no.1
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• pp.29-31
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• 2007

• Microbiology and Biotechnology Letters
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• v.44 no.3
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• pp.349-354
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• 2016

A variety of nuruks collected in different areas in Korea were explored to isolate sixty yeast strains that was able to grow at 44℃. MBY/L1569 strain, which showed the highest growth rate, was selected and identified as Pichia farinosa (Millerozyma farinosa). The isolated strain exhibited superior resistance to heat, acid, and alkali compared with those of P. farinosa KCTC27412 as a control strain. The specific growth rate of P. farinosa MBY/L1569 at 46℃ was 0.37 ± 0.05 h⁻¹, and the highest specific growth rate of 0.50 ± 0.02 h⁻¹ was obtained when it was grown at pH 7.0 and 37℃ with 50 g/l (w/v) glucose as the carbon source. Under optimum growth conditions, strain MBY/L1569 produced ethanol 19.66 ± 0.68 g/l from glucose 50 g/l, with an approximate yield of 40%. P. farinosa MBY/L1569 was deposited at the Korean Collection for Type Cultures as pichia farinosa KCTC27753.

• Journal of Applied Biological Chemistry
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• v.52 no.4
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• pp.163-169
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• 2009

A total of 155 microbial strains were isolated from the Korean traditional soybean paste based on their morphological features on the growth of agar plate. Among the isolated strains, a total of 28 strains were capable of hydrolyzing isoflavone glycoside to isoflavone aglycone efficiently in the soybean paste. Finally, two strains, K123-1 and SI, were selected because of their resistance to 15% NaCl and ability to convert isoflavone glycoside to isoflavone aglycone efficiently during the fermentation of soybean paste. The isolated strains K123-1 and SI were identified to be Pichia guilliermondii and Candida fermentati, respectively, using the partial 26S rDNA sequence analysis and phylogenic analysis. Pichia guilliermondii K123-1 and Candida fermentati SI converted daidzin to daidzein up to 96% and 95%, respectively, and genistin to genistein up to 92% when soybean pastes were fermented at $30^{\circ}C$ for 20 days with a single isolated strain. Pichia guilliermondii K123-1 and Candida fermentati SI were able to grow in the presence of 15% NaCl on both liquid medium and agar plate. We think that Pichia guilliermondii K123-1 and Candida fermentati SI might be one of good candidates for making functional soybean paste because they are isolated from the Korean traditional soybean paste and have a good ability to convert isoflavone glycosides to isoflavone aglycones and a high salt tolerance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1077-1082
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• 2007

In this study, killer yeasts were isolated from traditional Nuruk to improve storage and suppress contaminant in food industry. Among killer yeasts, yeast K15 showed strong killer toxin activity and inhibited growth of Salmonella Typhimurium and Vibrio parahaemolyticus. Killer yeast K15 was identified with Pichia anomala by the Microlog TM 4.0 identification system and homology of the ITS sequence. Killer toxin generated from P. anomala K15 was inactivated by pronase E and suggested to be a protein. Therefore killer toxin of P. anomala K15 was thought to be safe in human such as bacteriocin. P. anomala K15 was sufficient for growth in 50% glucose and could be used to prevent contaminant in initial stages of alcohol beverage fermentation.