Yeast sequencing reports. Comparison of INO1 gene sequences and products in Candida albicans and Saccharomyces cerevisiae

Abstract

The sequence of the Candida albicans inositol biosynthetic gene, CaINO1, and its flanking regions is determined in this study. The largest open reading frame has a coding sequence of 1560 base pairs, corresponding to a predicted protein of 521 amino acids. Three primary transcriptional start sites are found 64, 57 and 52 base pairs upstream of the ATG translational start site at position 1374. Five stop codons exist in a cluster at the end of the coding region. Within the upstream region TATA and CAAT eukaryotic regulatory sequences are identified along with regions corresponding to a 10 base pair inositol/choline responsive element consensus sequence. Computer analysis of the DNA sequence shows strong homology to the Saccharomyces cerevisiae INO1 gene. A comparison of the deduced amino acid sequence of the C. albicans INO1 gene product, inositol-1-phosphate synthase, with its homolog in S. cerevisiae shows 64% identity and 77% similarity. The differences between the two proteins are most prominent in the N-terminal regions.

Candida albicans Uses Multiple Mechanisms To Acquire the Essential Metabolite Inositol during Infection

“…The C. albicans homolog of ScINO1 identified by Klig et al (18) was disrupted in order to determine if it was required for inositol biosynthesis in C. albicans. The C. albicans INO1 homolog (orf19.7585) was disrupted by sequentially replacing both alleles of the gene with the NAT1-FLP cassette, which contains the nourseothricin resistance gene (39).…”

“…albicans carries a gene determined on the basis of sequence similarity to be a putative homolog of INO1; this gene (GenBank accession no. L22737) was identified and sequenced by Klig et al (17,18). C. albicans INO1 (CaINO1) shows 64% identity to ScINO1 at the amino acid level (18).…”

“…L22737) was identified and sequenced by Klig et al (17,18). C. albicans INO1 (CaINO1) shows 64% identity to ScINO1 at the amino acid level (18). In addition, it has been shown previously that C. albicans has potent inositol transporter activity (15).…”

Disruption ofINOS, a Gene Encodingmyo-Inositol Phosphate Synthase, Causes Male Sterility inDrosophila melanogaster

“…A precise deletion of the sole inositol biosynthetic gene, Inos , was generated. MIPS mutants have been reported in plants (Donahue et al 2010) and many unicellular organisms (Klig et al 1994; Molina et al 1999); this may be the first report examining the phenotype of a MIPS gene deletion in animals. Homozygous inos ΔDF deletion embryos hatch, but without dietary inositol, they die within a few hours as first-instar larvae.…”

“…The third is synthesis via a two-step process from glucose-6-phosphate, for which the first step is catalyzed by myo -inositol-3-phosphate synthase (MIPS) (Loewus and Kelly 1962; Eisenberg et al 1964). The properties and catalytic mechanisms of MIPS are similar in animals, plants and yeast (Chen and Charalampous 1964; Loewus et al 1983; Klig et al 1994; Molina et al 1999). Currently the genomes of more than one hundred organisms, ranging from microbes to man, contain annotated orthologs which encode MIPS (NCBI).…”