TABLE 1.

Genes disrupted in mutants identified in initial library screen

V-ATPase subunits and dedicated assembly factors	VMA1*, VMA2*, VMA3*, VMA5*, VMA6*, VMA8*, VMA10*, VMA12*,   VMA13*, VMA16*, VMA21*, VMA22*, VPH1*
Vacuolar protein sorting/vesicular transport	CLC1, SHP1, VPS15, VPS16, VPS34, VPS45, VPS54
Amino acid biosynthesis/transport	ARO1, CYS4*, GLY1, ILV1, TAT1, TRP1, TRP2, TRP3, TRP4, TRP5
Phosphate biosynthesis/metabolism	PHO2, PHO4, PHO81, PHO85
Signal transduction	CAK1, CKB2, PTC1
Transcription	ADA2, ADA3, CRZ1, RCS1, RPB4, SNF6, SNF5, SWI3, ZAP1
Cell wall function	CWH36, KRE1, RMD7
Other	ANP1 (glycosylation), CTR1 (high-affinity copper transport), KEX2*   (proteolytic processing), MAP1 (methionine aminopeptidase),   RIB4 (vitamin B2 biosynthesis), RNR1 (purine and pyrimidine   biosynthesis), TEF4 (translation)
Uncharacterized open reading frames	YBL006c, YDR114c, YEL045c, YJL175w, YKL118w, YMR031w-a, YOR331c   (dubious ORF opposite VMA4), YPL159c

Mutant strains that grew on YEPD medium buffered to pH 5, but failed to grow on YEPD medium buffered to pH 7.5 containing 60 mM CaCl₂, in two independent screens of the deletion mutant library are shown. The genes mutated in each strain are assigned a general function on the basis of information in the Saccharomyces Genome Database. Genes previously identified in screens for vma mutants are indicated by *.