Yeast mitochondria (Saccharomyces cerevisiae) contain Ca(2+)-independent phospholipase A1 and A2 activities: effect of respiratory state.
We demonstrate that both phospholipase A1 and phospholipase A2 are associated with isolated yeast mitochondria (Saccharomyces cerevisiae). Activity assays indicate that, unlike most other mitochondrial phospholipases A, the yeast enzymes are Ca(2+)-independent with acidic (pH 4-5) as well as alkaline (pH 8-9) pH optima. Data obtained with mitochondria isolated from either fermenting or respiring cells, and initial observations with a petite strain, strongly suggest that a phospholipase A2 with an acidic pH optimum functions in the in vivo adaptation and maintenance of mitochondrial membranes required for respiration.
Research Service, Department of Veterans Affairs Medical Center, Philadelphia, PA 19104.
R W
RW
Yost
S J
SJ
Grauvickel
R
R
Cantwell
J S
JS
Bomalaski
A P
AP
Hudson
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002455:Cell Division; D002855:Chromatography, Thin Layer; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008244:Lysophosphatidylcholines / Q000378:metabolism; D008928:Mitochondria / Q000201:enzymology* / Q000378:metabolism; D010101:Oxygen Consumption; D010713:Phosphatidylcholines / Q000378:metabolism; D010741:Phospholipases A / Q000378:metabolism*; D054466:Phospholipases A1; D054467:Phospholipases A2; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000378:metabolism; D014462:Ultrafiltration
D005230:Fatty Acids, Nonesterified; D008244:Lysophosphatidylcholines; D010713:Phosphatidylcholines; D010741:Phospholipases A; D054466:Phospholipases A1; D054467:Phospholipases A2; D005947:Glucose; D005990:Glycerol; D002118:Calcium