title: Occurrence of -SH containing molecules on the goat sperm external surface that are essential for flagellar motility.
abstract: p-Chloromercuriphenylsulphonic acid (PCMPS), a thiol reagent which is believed not to enter the cells, strongly inhibits motility of freshly extracted goat cauda-epididymal sperm preparations containing epididymal plasma (EP). The inhibitory action of PCMPS is not due to its interaction with the -SH groups of the surrounding EP-proteins. Washed cells when pretreated with low concentration of PCMPS (25 microM) for a short period (6 min) lost motility completely when assayed in presence of EP. PCMPS-mediated inhibition of motility cannot be reversed with the addition of large excess of various-SH compounds. The data suggest that PCMPS binds with high affinity to the specific -SH group(s) of sperm ecto-sulfhydryl molecules to cause their inactivation irreversibly by altering their conformation and thereby destroys sperm motility.
mesh_terms: D002731:4-Chloromercuribenzenesulfonate / Q000494:pharmacology; D000818:Animals; D003545:Cysteine / Q000494:pharmacology; D004229:Dithiothreitol / Q000494:pharmacology; D005033:Ethylmaleimide / Q000494:pharmacology; D006041:Goats; D008297:Male; D008623:Mercaptoethanol / Q000494:pharmacology; D013081:Sperm Motility / Q000187:drug effects; D013082:Sperm Tail / Q000187:drug effects*; D013094:Spermatozoa / Q000032:analysis* / Q000187:drug effects*; D013438:Sulfhydryl Compounds / Q000032:analysis*
chemical_list: D013438:Sulfhydryl Compounds; D002731:4-Chloromercuribenzenesulfonate; D008623:Mercaptoethanol; D003545:Cysteine; D005033:Ethylmaleimide; D004229:Dithiothreitol