• KSBB Journal
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• v.13 no.3
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• pp.325-330
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• 1998

The methylotrophic yeast, Pichia pastoris, is known to be a potential host to offer many advantages for production of recombinant proteins. Fermentation parameters were optimized to enhance the heterologous ${\beta}$-galactosidase productivity with P. pastoris. Optimum concentration of methanol, used as inducer, was observed to be 8 g/L and the extent of repression of AOX1 promoter by glycerol was lower than by glucose. The degradation of the gene product ${\beta}$-galactosidase by protease was inhibited as the pH increased from 5 to 8 and the yeast extract(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%). Induction method, in which methanol is just added to fermentation medium without centrifugation, was found to be as much effective as the one with centrifugation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.1
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• pp.62-64
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• 2004

The use of enantioselective hydrolysis for preparing chiral epichlorohydrins was investigated using recombinant Pichia pastoris with the enantioselective epoxide hydrolase of Rhodotorula glutinis. The rate of the recombinant epoxide hydrolase-catalyzed enantioselective hydrolysis of racemic epichlorohydrins was enhanced by the addition of 5%(v/v) Tween 20. Enantiopure (R)-epichlorohydrins with an enantiopurity of 100% ee and a yield of 26% were obtained within 5min from 50mM racemates.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.87-93
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• 2016

From 182 non-pathogenic wild yeast isolates from flowers, Pichia silvicola UL6-1 and Sporobolomyces carnicolor 402-JB-1 were selected for potent ${\gamma}$-aminobutyric acid production and microbiological characteristics were investigated. Pichia silvicola UL6-1 formed ascospores and pseudomycelia. The strain was also halotolerant, growing well in 5% NaCl-containing yeast extract-peptone-dextrose (YPD) medium. Sporobolomyces carnicolor 402-JB-1 did not form ascospores or pseudomycelia and grew well on 10% glucose-yeast extract-peptone medium.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1695-1699
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• 2007

Ferritin is an iron storage protein found in most living organisms as a natural assembled macromolecule. For studying the functional ability of the ferritin assembly, human H- and L-ferritins were expressed and purified from Pichia pastoris strain GS115. The recombinant H- and L-ferritins showed a globular form with transmission electron microscopy. The rate of iron uptake for H-ferritin was significantly faster than that for the L-ferritin in vitro. By gel permeation chromatography analysis, recombinant ferritins were confirmed as multimeric subunits with high molecular weight and it was indicated that assembled subunits were able to store iron in vivo.

• Journal of Microbiology and Biotechnology
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• v.25 no.11
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• pp.1902-1907
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• 2015

This study is the first report of the entire nucleotide sequence of an inositol phosphoceramide synthase gene from the stress-tolerant yeast Pichia kudriavzevii (PkAUR1). Sequence analysis revealed an open reading frame that spans 1,443 bp and encodes a 480-amino-acid-residue protein with the highest sequence similarity (41.7%) to Aur1 from Spathaspora passalidarum. A phenotypic assay with transformed S. cerevisiae and P. kudriavzevii indicated that two amino acid residues, Phe166 and Gly249, play crucial roles in the resistance to aureobasidin A, which is consistent with previous reports for other fungal Aur1s. The GenBank Accession No. for PkAUR1 is KP729614.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.498-502
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• 2016

3'-Hydroxygenistein can be obtained from the biotransformation of genistein by the engineered Pichia pastoris X-33 strain, which harbors a fusion gene composed of CYP57B3 from Aspergillus oryzae and a cytochrome P450 oxidoreductase gene (sCPR) from Saccharomyces cerevisiae. P. pastoris X-33 mutants with higher 3'-hydroxygenistein production were selected using a periodic hydrogen peroxide-shocking strategy. One mutant (P2-D14-5) produced 23.0 mg/l of 3'-hydroxygenistein, representing 1.87-fold more than that produced by the recombinant X-33. When using a 5 L fermenter, the P2-D14-5 mutant produced 20.3 mg/l of 3'-hydroxygenistein, indicating a high potential for industrial-scale 3'-hydroxygenistein production.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1202-1207
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• 2012

A gene, ClCDA, encoding chitin deacetylase from Colletotrichum lindemuthianum, was optimized according to the codon usage bias of Pichia pastoris and synthesized in vitro by overlap extension PCR. It was secretorily expressed in P. pastoris GS115 using the constitutive expression vector pHMB905A. The expression level reached the highest with 110 mg/l culture supernatant after 72 h of methanol induction, which comprised 77.27 U/mg chitin deacetylase activity. SDS-PAGE, mass spectrometry, and deglycosylation assays demonstrated that partial recombinant protein was glycosylated with an apparent molecular mass of 33 kDa. The amino acid sequences of recombinant proteins were confirmed by mass spectrometry.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.202-205
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• 2005

Our previous study showed that the overexpression of carboxypeptidase Y (CPY) of Saccharomyces cerevisiae in Escherichia coli resulted in the formation of insoluble inclusion bodies. To produce soluble CPY, we designed a novel Pichia pastoris expression system, in which the following were inserted into expression vectors: three different signal sequences derived from the mating factor a1 of S. cerevisiae, an inulinase of Kluyveromyces marxianus, and the endogenous signal sequence of CPY. The expression vector pHIL-D2-SSinul-proCPY was the most effective in the production of proCPY among the vectors examined. The purified active CPY was obtained from proCPY by treating with proteinase K, followed by QExcellose ion-exchange column chromatography.

• Mycobiology
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• v.39 no.2
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• pp.121-124
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• 2011

The cDNA of endo-1,$4-{\beta}-xylanaseA$, isolated from Phaenerocheate chrysosporium was expressed in Pichia pastoris. Using either the intrinsic leader peptide of XynA or the ${\alpha}$-factor signal peptide of Saccharomyces cerevisiae, xylanaseA is efficiently secreted into the medium at maximum concentrations of 1,946 U/L and 2,496 U/L, respectively.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.159-162
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• 2007

Optimization of the fermentation medium for phenylethyl alcohol (PEA) production by Pichia anomala SKM-T was performed. The carbon source (glucose), nitrogen source (L-phenylalanine), and initial pH value were independent variables of the optimized medium. The central composite rotatable design was used for the experimental design and the analysis of the results. The optimum medium composition for the maximal production (621.27 mg/L) of PEA was found to be an initial pH of 5.03, and concentrations of L-phenylalanine at 6.53 and glucose at 6.11 g/L (w/v). This experimental finding is in close agreement with the model prediction (702.79 mg/L; desirability 0.884) with an 11.6% difference.