TABLE 1.

Enzymatic activities and genes required for cell wall polymer synthesis and remodeling in S. cerevisiae

ProcessActivityaGenebProtein function/comment
β-1,3-Glucan synthesisβ-1,3-GS FKS1 Catalytic subunit of β-1,3-glucan synthase
GSC2 Catalytic subunit of β-1,3-glucan synthase
RHO1 GTP-binding protein, regulatory subunit of β-1,3-glucan synthase
FKS3 Protein with similarity to Fks1p and Gsc2p
β-1,6-Glucan synthesisβ-1,6 GS RHO1 Probable regulatory subunit of β-1,6-synthase
Unknown BIG1 ER membrane protein required for cell wall β-1,6-glucan synthesis
KRE1 Cell wall glycoprotein involved in β-glucan assembly
KRE5 UGGT-related protein required for β-1,6-glucan biosynthesis
KRE6 Protein required for β-1,6-glucan biosynthesis
KRE9 Glycoprotein involved in cell wall β-glucan assembly
KNH1 Kre9p homologue
ROT1 Protein required for cell wall function
SKN1 Type II membrane protein with similarity to Kre6p
Chitin synthesisCSI CHS1 Required for repairing the chitin septum after separation
CSII CHS2 Makes chitin in the primary septum during cytokinesis
CSIII CHS3 Makes the majority of cell wall chitin, the chitin ring during bud emergence, and spore wall chitosan
SKT5 Activator of Chs3p, recruits Chs3p to the bud neck via an interaction with Bni4p
SHC1 Sporulation-specific activator of Chs3p with similarity to Skt5p
Chitosan synthesisChitin deacetylase CDA1 Involved in biosynthesis of ascospore wall chitosan
CDA2 Involved in biosynthesis of ascospore wall chitosan
Protein mannosylationα-1,6-MT OCH1 N-glycan outer chain initiation
α-1,2/6-MT MNN9 ManPol I and II subunits involved in N glycosylation
α-1,6-MT VAN1 ManPol I subunit involved in N glycosylation
ANP1 ManPol II subunit involved in N glycosylation
HOC1 ManPol II subunit involved in N glycosylation
MNN10 ManPol II subunit involved in N glycosylation
MNN11 ManPol II subunit involved in N glycosylation
α-1,3-MT MNN1 Involved in N glycosylation termination and O mannosylation
α-1,2-MT MNN2 Branching of outer chain of N glycosylation
MNN5 N-glycan outer chain extension
MNT2 α-1,3-Mannosyltransferase involved in O mannosylation
MNT3 α-1,3-Mannosyltransferase involved in O mannosylation
α-1,2 MT KRE2 KTR family member involved in N and O glycosylation
KTR1 KTR family member involved in N and O glycosylation
MT KTR2 KTR family member involved in N and O glycosylation
KTR3 KTR family member involved in N and O glycosylation
YUR1 KTR family member involved in N and O glycosylation
KTR4 Putative mannosyltransferase
KTR5 Putative mannosyltransferase
KTR7 Putative mannosyltransferase
α-1,2-MpT KTR6 α-1,2-Mannosylphosphate transferase involved in N glycosylation
Glucan processing/remodelingβ-1,3-Glucan elongase GAS1 β-1,3-Glucanosyltransferase
Exo-β-1,3/1,6-glucanase EXG1 Major exo-β-1,3-glucanase of the cell wall
EXG2 GPI-anchored plasma membrane exo-β-1,3-glucanase
SPR1 Sporulation-specific exo-β-1,3-glucanase
Endo-β-1,3-glucanase BGL2 Can link in vitro β-1-3-glucan chains through a β-1,6-linkage
DSE4 Involved in septum degradation
Glucanase like DSE2 Glucanase-like secreted protein involved in septum degradation
EGT2 GPI-anchored cell wall endoglucanase required for proper cell separation after cytokinesis
GAS2 GAS family member
GAS3 GAS family member
GAS4 GAS family member
GAS5 GAS family member
SCW3 Glucanase-like “soluble” cell wall protein
SCW4 Glucanase-like “soluble” cell wall protein
SCW10 Glucanase-like “soluble” cell wall protein
SCW11 Glucanase-like protein
Chitin processingChitinase CTS1 Endochitinase, required for cell separation after mitosis
CTS2 Sporulation-specific endochitinase-like protein
Glucan/chitin cross-linkingTransglycosidase CRH1 Putative glycosidase of the cell wall
UTR2 Putative GPI-anchored glycosidase localized to the bud neck
CRR1 Protein with similarity to Crh1p
  • a MT, mannosyltransferase; MpT, mannosylphosphate transferase.

  • b Genes whose products have no known or established enzymatic activity are in boldface.