Characterization of the CaENG1 gene encoding an endo-1,3-beta-glucanase involved in cell separation in Candida albicans.
The Candida albicans CaENG1 gene encoding an endo-1,3-beta-glucanase was cloned by screening a genomic library with a DNA probe obtained by polymerase chain reaction using synthetic oligonucleotides designed according to conserved regions found between two Saccharomyces cerevisiae endo-1,3-beta-glucanases (Eng1p and Eng2p). The gene contains a 3435-bp open reading frame (ORF), capable of encoding a protein of 1145 amino acids (124,157 Da), that contains no introns. Comparison of the ScEng1p sequence with partial C. albicans genomic sequences revealed the presence of a second protein with sequence similarity (the product of the Ca20C1.22c ORF, which was named CaENG2). Disruption of the CaENG1 gene in C. albicans had no dramatic effects on the growth rate of the strains, but it resulted in the formation of chains of cells, suggesting that the protein is involved in cell separation. Expression of CaENG1 in S. cerevisiae cells afforded a 12-fold increase in the 1,3-beta-glucanase activity detected in culture supernatants, showing that the protein has similar enzymatic activity to that of the S. cerevisiae Eng1p. In addition, when the C. albicans protein was expressed under its native promoter in S. cerevisiae eng1 mutant cells, it was able to complement the separation defect of this mutant, indicating that these two proteins are true functional homologues.
Esteban
Pedro Felipe
PF
Departamento de Microbiología y Genética, Instituto de Microbiología Bioquímica, Campus Miguel de Unamuno, CSIC/Universidad de Salamanca, Salamanca 37007, Spain.
Ríos
Inmaculada
I
García
Raúl
R
Dueñas
Encarnación
E
Plá
Jesús
J
Sánchez
Miguel
M
de Aldana
Carlos R Vázquez
CR
Del Rey
Francisco
F
D000595:Amino Acid Sequence; D002176:Candida albicans / Q000201:enzymology / Q000235:genetics* / Q000502:physiology; D002455:Cell Division; D003001:Cloning, Molecular; D017124:Conserved Sequence; D004271:DNA, Fungal / Q000235:genetics; D005656:Fungal Proteins; D005816:Genetic Complementation Test; D016681:Genome, Fungal / Q000235:genetics; D043326:Glucan 1,3-beta-Glucosidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004693:Glucan Endo-1,3-beta-D-Glucosidase / Q000235:genetics; D007438:Introns; D008969:Molecular Sequence Data; D009024:Morphogenesis / Q000235:genetics; D016254:Mutagenesis, Insertional; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D017386:Sequence Homology, Amino Acid
D004271:DNA, Fungal; D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; C470563:ACF2 protein, S cerevisiae; C470562:DSE4 protein, S cerevisiae; D004693:Glucan Endo-1,3-beta-D-Glucosidase; D043326:Glucan 1,3-beta-Glucosidase