From the culture filtrates of C. albicans, C. tropicalis and C. parapsilosis, proteinases were purified using a series of chromatographic steps consisting of DEAE-Sepharose, Sephacryl S-200 and size-exclusion HPLC which removed contaminating mannoproteins and extraneous proteins. Anti-Candida proteinase antibodies in sera from mice infected with various Candida species were detected using ELISA for serodiagnosis of candidiasis. Three proteinases were blotted by homologous and heterologous anti-proteinase antisera on Western blot analysis. All sera from six Candida species-infected mice were reactive with proteinases of C. albicans, C. tropicalis, and C. parapsilosis, although C. glabrata, C. guilliermondii, and C. krusei did not secrete proteinase. The seroreactivities of proteinase with sera from mice infected with homologous C. albicans and C. tropicalis were higher than those with sera from heterologous Candida species-infected mice. These results suggest that three proteinases have at least one common epitope, but its application for diagnosis of candidiasis should be considered with limits of specificity.
Animal ; Candida/genetics* ; Candida/enzymology* ; Candidiasis/enzymology* ; Endopeptidases/analysis* ; Female ; Mice ; Mice, Inbred ICR ; Species Specificity

Yeast surface display involves that the exogenous protein, which was fused with the yeast outer shell cell wall protein, was genetically anchored on the yeast cell surface. It has been widely used in expression and screening of functional protein. Here, we focused on the construction of lipase-displaying systems and its application in enzymatic biosynthesis, such as fatty acid methyl esters, short-chain flavour esters and sugar esters applications, and so on.
Candida ; enzymology ; genetics ; Lipase ; biosynthesis ; genetics ; Pichia ; enzymology ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Solvents ; Yeasts ; enzymology ; genetics

Candida albicans produced a karatinolytic proteinase (KPase) or C. albicans producing proteinase (CAPP), a proposed new term for this enzyme, and Trichophyton mentagrophytes also produced KPase when cultivated in liquid medium containing human stratum corneum (HSC) as the nitrogen source, but were unable to do so when cultivated in sabouraud dextrose broth. Purified KPase from the culture supernatants of C. albicans had a molecular weight of 42,000 and an optimum pH at 4.0. The KPase was found to belong to the carboxyl proteinases group and its activity was strongly inhibited by pepstatin. Both fungi were able to grow by secreting KPase which digested HSC for nutrients. KPase from both fungi had high activity in each optimum pH, such as weakly acidic pH on C. albicans and neutral pH on T. mentagrophytes to adapt their surrounding environment by changing the environmental pH into their own optimum pH.
Candida albicans/*enzymology/growth & development ; Culture Media ; Endopeptidases/*physiology ; Hydrogen-Ion Concentration ; Molecular Weight ; Trichophyton/*enzymology/growth & development

The synthesis of vitamin A plamitate in organic solvent with vitamin A acetate and ethyl palmitate with immobilized lipase from Candida sp. was studied. The influences of solvent, the molar ratio of substrates, the reaction temperature and time, and the water concentration were optimized and the best result was obtained by transesterification from 0.100 g vitamin A acetate and 0.433 g ethyl palmitic, at 30 degrees C, in 10 mL petroleum ether, containing 0.2% of water (V/V), with 1.1 g lipase. In these conditions, the yield of vitamin A palmitate reached 83% in 12 h. The immobilized lipase was reused about 5 batches.
Candida ; enzymology ; Catalysis ; Enzymes, Immobilized ; metabolism ; Lipase ; metabolism ; Vitamin A ; analogs & derivatives ; chemical synthesis

L-2-aminobutyric acid (L-ABA) is an important chemical raw material and chiral pharmaceutical intermediate. The aim of this study was to develop an efficient method for L-ABA production from L-threonine using a trienzyme cascade route with Threonine deaminase (TD) from Escherichia. coli, Leucine dehydrogenase (LDH) from Bacillus thuringiensis and Formate dehydrogenase (FDH) from Candida boidinii. In order to simplify the production process, the activity ratio of TD, LDH and FDH was 1:1:0.2 after combining different activity ratios in the system in vitro. The above ratio was achieved in the recombinant strain E. coli 3FT+L. Moreover, the transformation conditions were optimized. Finally, we achieved L-ABA production of 68.5 g/L with a conversion rate of 99.0% for 12 h in a 30-L bioreactor by whole-cell catalyst. The environmentally safe and efficient process route represents a promising strategy for large-scale L-ABA production in the future.
Aminobutyrates ; chemical synthesis ; Bacillus thuringiensis ; enzymology ; Candida ; enzymology ; Escherichia coli ; enzymology ; Formate Dehydrogenases ; metabolism ; Leucine Dehydrogenase ; metabolism ; Threonine ; metabolism ; Threonine Dehydratase ; metabolism

Lipase from Candida sp. 99-125 was immobilized by physical adsorption onto macroporous resins. The results showed that the nonpolar resin NKA was the best carrier used in low aqueous media. 98.98% of degree of immobilization can be achieved when the adsorption procedure was performed in the presence of heptane. The hydrolytic activity and the apparent activity recovery of lipase adsorbed on resin in heptane was 4.07 and 3.43 times higher than that of lipase adsorbed in sodium phosphate buffer, respectively. The catalytic properties of immobilized lipase for production of biodiesel in low aqueous media were studied. Immobilized lipase displayed the highest activity when the crude enzyme/resin weight ratio was 1.92:1 and the water content(water/oil weight ratio) was 15% at 40 degrees C under pH 7.4. As lipase was adsorbed on NKA in heptane to produce biodiesel, the batch conversion rate can reach 97.3% when a three-step methanolysis protocol was used. After 19 consecutive batches, the conversion rate remained 70.2%.
Candida ; enzymology ; Enzymes, Immobilized ; metabolism ; Gasoline ; Lipase ; isolation & purification ; metabolism ; Porosity ; Resins, Synthetic ; chemistry ; Soybean Oil ; chemistry

One yeast strain, which was isolated from 256 natural samples, was found to be able to utilize D-xylose effectively. On the basis of assimilation physiological and molecular biological tests, the yeast strain was identified as a strain of Candida tropicalis. Furthermore, metabolic engineering breeding strategy was applied to change the metabolic flux in order to increase ethanol productivity. In this study, the C. tropicalis was used as the host strain and the plasmid pYX212-XYL2, which was formerly constructed for over expression of XYL2 gene encoding xylitol dehydrogenase (XDH) from Pichia stipitis, was used as the backbone of the recombinant vector. A hygro gene was inserted into downstream position of XYL2 gene, meanwhile, the result plasmid pXY212-XYL2-Hygro transformed into C. tropicalis by electroporation. Thus, a recombinant yeast C. tropicalis XYL2-7 was obtained through hygromycin B resistance screening and its specific XDH activity was 0.5 u/mg protein, which was 3 times more than that of the parent strain. Additionally, the recombinant yeast was applied in the fermentation of xylose. Compared with the parent yeast, it was concluded that the xylitol yield in the broth decreased by 3 times, however, the ethanol yield increased by 5 times. The feasibility of ethanol production from xylose by C. tropicalis was firstly studied in this paper. These research results are helpful to advance the bioconversion of renewable resources (e. g. straw, wheat bran, and husk) to fuel ethanol.
Candida tropicalis ; genetics ; metabolism ; D-Xylulose Reductase ; genetics ; metabolism ; Electroporation ; Ethanol ; metabolism ; Fermentation ; Pichia ; enzymology ; genetics ; Recombination, Genetic ; Xylose ; metabolism

Short-chain esters play a significant role in the food industry as flavor and aroma constituents. Candida antarctica lipase B (CALB) is one of the most effective catalysts for organic synthesis. We constructed a CALB-displaying yeast whole-cell biocatalyst and applied it to esterification from caproic acid and ethanol. CALB was fused with the alpha-agglutinin C-terminal and the signal peptide of Glucoamylase in pICAS, a yeast surface display vector, to construct plasmid pICAS-CALB. An extremely Asn-rich linker, named celAL was inserted in the Xho I of pICAS-CALB to construct plasmid pICAS-celAL-CALB. The fused gene was under the control of GAPDH promoter. After incubated at 30 degrees C for 96 h the lipase hydrolytic activity of the yeast whole cells reached a plateau, 26.26 u/(g x dry cell). In nonaqeous media, the yield of 98.0% ethyl hexanoate was obtained after 24 h esterification from caproic acid and ethanol (the molar ratio of caproic acid : ethanol = 1 : 1.25) using lyophilized CALB displaying yeast whole cells.
Biocatalysis ; Candida ; enzymology ; Caproates ; metabolism ; Cloning, Molecular ; Fungal Proteins ; Genetic Engineering ; Lipase ; biosynthesis ; genetics ; Saccharomyces cerevisiae ; genetics ; metabolism

OBJECTIVETo investigate the genotypic profiles of Candida albicans isolates from erosive oral lichen planus (OLP) and nonerosive OLP, and then to compare the results with their virulence attributes.

METHODSA total of 112 isolates from healthy control (26), erosive OLP (62) and nonerosive OLP (24) were screened for genotypic profiles by using the randomly amplified polymorphic DNA (RAPD) assay. In addition, adhesion to buccal epithelial cells assay and phospholipase activity assay were used to evaluate the virulence attributes of these isolates.

RESULTSRAPD analyses with some random primer revealed 4 different genotypes among all isolates, and there was significant difference in the geneotypic constitution between every two groups. Statistically, in healthy group the major type was B and D, however, the major type in erosive OLP was A and C, and the major type in nonerosive OLP was A and D. The isolates with genotype A had the strongest adherence among 4 genotypes. The phospholipase activity of the isolates with genotype A and C were higher than that with genotype B and D.

CONCLUSIONSSome Candida albicans isolates with special genotypic profiles and virulence attributes may contribute to the development and progression of OLP.

Adhesiveness ; Candida albicans ; classification ; enzymology ; physiology ; Genotype ; Humans ; Lichen Planus, Oral ; microbiology ; Phospholipases ; metabolism ; Random Amplified Polymorphic DNA Technique

This paper reports the progress of biodiesel production with enzymatic catalysis in Beijing University of Chemical Technology, one of the leaders in biodiesel R & D in China, which includes screening of high-yield lipase production strains, optimization and scale-up of the lipase fermentation process, lipase immobilization, bioreactor development and scale-up, biodiesel separation and purification and the by-product glycerol utilization. Firstly, lipase fermentation was carried out at industrial scale with the 5 m3 stirred tank bioreactor, and the enzyme activity as high as 8 000 IU/mL was achieved by the species Candida sp. 99-125. Then, the lipase was purified and immobilized on textile membranes. Furthermore, biodiesel production was performed in the 5 m3 stirred tank bioreactor with an enzyme dosage as low as 0.42%, and biodiesel that met the German biodiesel standard was produced. And in the meantime, the byproduct glycerol was used for the production of 1,3-propanediol to partly offset the production cost of biodiesel, and 76.1 g/L 1,3-propanediol was obtained in 30 L fermentor with the species Klebsiella pneumoniae.
Biofuels ; Bioreactors ; Biotechnology ; economics ; methods ; Candida ; enzymology ; Catalysis ; China ; Enzymes, Immobilized ; metabolism ; Esterification ; Fermentation ; Lipase ; metabolism ; Plant Oils ; chemistry