The S. cerevisiae structural gene for chitin synthase is not required for chitin synthesis in vivo

Bulawa, Christine E.; Slater, Martin L.; Cabib, Enrico; Au-Young, Janice; Sburlati, Adriana; Adair, W. Lee; Robbins, Phillips W.

doi:10.1016/0092-8674(86)90738-5

Cited by 258 publications

(196 citation statements)

References 46 publications

Supporting

Mentioning

186

Contrasting

Unclassified

Order By: Relevance

“…In S. cerevisiae, the CHS3 (CSD2) gene product is responsible for the synthesis of most of the chitin in the cell wall (9,10). Northern blot analysis ofall three chitin synthase In support of previous findings, the virulence of auxotrophic mutants was severely attenuated compared to prototrophic strains in an otherwise isogenic background (25,26,35). However, the virulence of the homozygous Aichs2::hisG mutant was only marginally attenuated compared to the heterozygote, which is phenotypically Chs2+.…”

Section: Discussionsupporting

confidence: 63%

“…(Table 2). In certain conditions, buds of S. cerevisiae chsl mutants lyse and appear refractile under phase-contrast optics (25). Bud lysis has been shown to be due to the action ofa chitinase with an acidic pH optimum and it was prevented by buffering of the medium to pH >5.0 (26,27).…”

Section: Methodsmentioning

confidence: 99%

“…cerevisiae, chsl mutants have a normal chitin content but have an increased tendency to undergo bud lysis in some media (10,(25)(26)(27). In this yeast, chs2 mutants often have aberrant morphologies and have a normal or increased chitin content but apparently lack the chitinous primary septum upon which the bulk of the chitin containing bud and birth scar material is assembled (10,32,33).…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

A hyphal-specific chitin synthase gene (CHS2) is not essential for growth, dimorphism, or virulence of Candida albicans.

Gow

Robbins

Lester

et al. 1994

Proc. Natl. Acad. Sci. U.S.A.

144

139

View full text Add to dashboard Cite

In the dimorphic fungus Cad Chitin is a fibrous polymer off-1,4-N-acetylglucosamine that constitutes a major structural component of the cell wall of many species of fungi, including those species that are pathogenic in humans. Because chitin is not found in mammals and its biosynthesis is normally essential for the shape and viability of the fungal cell (1, 2), chitin synthesis is an attractive target for the design of antifungal drugs. The most common medical mycosis is caused by Candida albicans, which is a diploid organism with no sexual cycle. This fungus is capable ofdimorphic growth where growth can occur by unicellular budding or filamentous hyphal extension and branch formation (3). The hyphal cell wall has three to five times the chitin content of the yeast cell wall (4, 5) and the cells have up to 10 times the in vivo chitin synthase activity (6). Three genes encoding chitin synthases have been cloned and sequenced in C. albicans (7,8,37). Two encode chitin synthase zymogens (CHSI and CHS2), homologous to the CHS genes of Saccharomyces cerevisiae. The third chitin synthase gene, CHS3, is homologous to the S. cerevisiae CSD2 (9) gene (also called CALI) and is apparently the structural gene for an enzyme, which in S. cerevisiae, does not require proteolysis for its activity. Northern blot analysis of the C. albicans CHS genes showed that CHS2 mRNA levels were elevated in cells undergoing hyphal development, whereas the CHS1 mRNA was expressed only at low levels early in germ-tube formation (8).The role of each of the chitin synthase activities described in S. cerevisiae has been investigated by disrupting each of the relevant genes (for a review, see ref. 10). Gene disruptions are more difficult in C. albicans because the organism is constitutively diploid and because stable multiply marked strains are required for sequential gene disruptions. Sequential gene disruption of HEM3 of C. albicans has been achieved with two genetic markers (11), but host strains with sufficient markers for the disruption of more than one structural gene are not yet available. In this study, we employed the "ura-blaster" protocol originally described by Alani et al.(12) for use with S. cerevisiae, to disrupt all alleles of the hyphal-specific C. albicans CHS2 gene. This method allows the sequential disruption of target alleles. by using Ura3 auxotrophy as a single selectable marker. Because the selectable marker can be regenerated after the disruption of each allele, this method overcomes the need for multiply marked host strains and is, therefore, ideally suited for the analysis of families of genes such as the CHS genes in C. albicans. We show that the chs2 null mutant was still able to form germ tubes, albeit with a reduced chitin content compared with the isogenic wild-type parent. A prototrophic chs2-null mutant was still able to cause disease in normal and immunosuppressed mice and had a similar virulence to the parental CHS2 strain. A preliminary report of the construction of the Achs2::hisG null mutant has a...

show abstract

Section: Discussionsupporting

confidence: 63%

Section: Methodsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

A hyphal-specific chitin synthase gene (CHS2) is not essential for growth, dimorphism, or virulence of Candida albicans.

Gow

Robbins

Lester

et al. 1994

Proc. Natl. Acad. Sci. U.S.A.

144

139

View full text Add to dashboard Cite

show abstract

“…2) Some chitin synthase genes have been cloned from S. cerevisiae (CHSl, CHS2, and CHS3), [3][4][5] Candida albicans (CHSl, CHS2, and CHS3) , 6 -8) and Neurospora crassa (chs-l).9) In S. cerevisiae, the three gene products have distinct functions. Chs2 participates in the formation of primary septa between mother and daughter cells,10) Chsl repairs the cell walls of daughter cells excessively degraded by chitinase when cell separation occurs, 11) and Chs3 forms over 90% of the cell wall chitin, deposits chitin in cdc mutants, deposits chitin in responce to ~-mating pheromone, and forms chitin as a precursor of chitosan in the spore wa11.…”

mentioning

confidence: 99%

Isolation and Characterization of Two Chitin Synthase Genes ofRhizopus oligosporus

Motoyama

Sudoh

Horiuchi

et al. 1994

Bioscience, Biotechnology, and Biochemistry

View full text Add to dashboard Cite

“…Two chitin synthases have been found in the yeast Saccharomj*ces ceret'isiae, chitin synthase 1 (Chsl) (Kang et al, 1984;Bulawa et al, 1986) and chitin synthase 2 (Chs2) Orlean, 1987). Recently a third synthase (Chs3) has been detected (Bulawa & Osmond, 1990).…”

Section: Introductionmentioning

confidence: 99%

Chitinase and chitin synthase 1: counterbalancing activities in cell separation of Saccharomyces cerevisiae

Cabib¹,

Sj²,

Shaw

1992

Journal of General Microbiology

142

View full text Add to dashboard Cite

The S. cerevisiae structural gene for chitin synthase is not required for chitin synthesis in vivo

Cited by 258 publications

References 46 publications

A hyphal-specific chitin synthase gene (CHS2) is not essential for growth, dimorphism, or virulence of Candida albicans.

A hyphal-specific chitin synthase gene (CHS2) is not essential for growth, dimorphism, or virulence of Candida albicans.

Isolation and Characterization of Two Chitin Synthase Genes ofRhizopus oligosporus

Chitinase and chitin synthase 1: counterbalancing activities in cell separation of Saccharomyces cerevisiae

Contact Info

Product

Resources

About