Phylogenetic identification of n-alkane assimilating Candida yeasts based on nucleotide divergence in the 5' end of LSU rDNA gene.

Abstract

Phylogenetic relationships of several species within the n-alkane assimilating Candida yeasts were investigated by using characters from the nucleotide sequence of the variable D1/D2 region at the 5' end of a large-subunit (26S) ribosomal DNA (rDNA) gene. First the nucleotide sequences of D1/D2 domain of Candida sp. 1098 (formerly identified as C. tropicalis 1098) and its dicarboxylic acid-producing-mutant strain M1210 were investigated. These two nucleotide sequences were identical and lacked only one base pair compared with that of C. maltosa CBS 5611 (type strain), and they were identified as C. maltosa. We then showed that C. maltosa IFO 1978 (formerly identified as C. cloacae) and C. maltosa IFO 1975 (formerly identified as C. subtropicalis) had the same nucleotide sequence and had only one base pair substitution compared with C. maltosa CBS 5611 (type strain), which is consistent with conventional classification. We also found that another widely studied n-alkane assimilating Candida yeast, C. tropicalis pk233, to be C. viswanathii.

Enhanced induction of cytochromes P450alk that oxidize methyl-ends of n-alkanes and fatty acids in the long-chain dicarboxylic acid-hyperproducing mutant of Candida maltosa

“…Brassylic acid (1,13‐tridecanedioic acid), the valuable base material for musk perfumes, has been commercially produced by fermentation from n ‐tridecane in which DCA‐hyperproducing mutant yeast strains were employed (Uemura, 1985). The original DCA‐producing yeast strain 1098, which produce <5 gL −1 of brassylic acid from n ‐tridecane in jar fermenter cultivation, was isolated from the soil of a petroleum refinery field and later identified as Candida maltosa (Arie et al , 2000). The DCA‐hyperproducing mutant strains such as M2030 (Uemura, 1985) and industrial strain M1210 (Atomi et al , 1994), which produce up to 125 and 165 gL −1 of brassylic acid from n ‐tridecane in jar fermenter cultivation, respectively, were generated from the wild‐type strain 1098 through repeated mutagenesis and screening for higher DCA production without determining mutation points.…”

Identification and Characterization of a Gene Encoding an ABC Transporter Expressed in the Dicarboxylic Acid-Producing YeastCandida maltosa

“…The n-alkane-assimilating yeast Candida maltosa strain 1098 has been isolated as a microbe that produces dodecanedioic acid from n-dodecane. 1,2) It produced 1.4 g/L of brassylic acid, a DCA of 13 carbons, from n-tridecane, when cultivated in a flask. By repeated mutagenesis, a mutant strain, C. maltosa M2030, that produced 125 g/L of brassylic acid in the media has been established.…”

“…By repeated mutagenesis, a mutant strain, C. maltosa M2030, that produced 125 g/L of brassylic acid in the media has been established. 1,2) In n-alkane-assimilating yeasts, n-alkanes are hydroxylated to fatty alcohols in the endoplasmic reticulum (ER) membrane by cytochromes P450ALK belonging to the CYP52 family. [3][4][5][6][7][8][9][10] Fatty alcohols are sequentially oxidized to fatty acids, which are used in the synthesis of membrane or storage lipids or are degraded by -oxidation in the peroxisome.…”