Activation of palmitic acid by human spermatozoa.
Human spermatozoa were studied to determine if a long chain fatty acid, CoASH ligase (AMP) (E.C. 6.2.1.3), was present. Ligase activity was measured with a radioligand millipore filter technique and was readily detectable in spermatozoa or in the protein fraction extracted with Triton X-100, but was not present in seminal plasma. The assay was optimized for pH, protein concentration, and incubation time. Activity was dependent upon palmitic acid, ATP, coenzyme A, and a divalent cation. Sperm ligase appeared similar to the ligase characterized from other tissues by sharing a common pH optimum (approximately 8.0-8.4), and a preference for magnesium over manganese in the incubation media.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D001711:Biotransformation; D002413:Cations, Divalent; D003066:Coenzyme A Ligases / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000378:metabolism; D008297:Male; D017830:Octoxynol; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism*; D011092:Polyethylene Glycols; D011869:Radioligand Assay; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D012661:Semen / Q000201:enzymology; D013094:Spermatozoa / Q000201:enzymology*; D013696:Temperature; D013997:Time Factors; D000098859:Long-Chain-Fatty-Acid-CoA Ligase
D002413:Cations, Divalent; D010169:Palmitic Acids; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D019308:Palmitic Acid; D011092:Polyethylene Glycols; D000255:Adenosine Triphosphate; D017830:Octoxynol; D003066:Coenzyme A Ligases; C090799:FAA2 protein, S cerevisiae; D000098859:Long-Chain-Fatty-Acid-CoA Ligase; D008274:Magnesium