biostudies-literatureQi Qnational natural science foundation of chinanatural science foundation of tianjin municipal science and technology commissionShanghai Municipal Science and Technology Commissionshanghai municipal commission of economy and informatizationshanghai municipal health and health commission clinical research project3175-3193https://www.ebi.ac.uk/biostudies/studies/S-EPMC8666411biostudies-literatureUnknown38(12)Oxidative stress is one of the major causes leading to male infertility including asthenozoospermia. Hydrogen sulfide (H₂S) has been widely recognized to be a potent antioxidant whose role is partially implemented by protein S-sulfhydration. However, protein S-sulfhydration has not been reported in germ cells. Therefore, we investigated whether asthenozoospermia could be associated with sperm protein S-sulfhydration. S-sulfhydrated proteins in human sperm were enriched via biotin-switch assay and analyzed using LC-MS/MS spectrometry. Two hundred forty-four S-sulfhydrated proteins were identified. Importantly, we validated that sperm histones H3.1 and H3.3 were the S-sulfhydrated proteins. Their S-sulfhydrated amino acid residue was Cysteine111. Abundances of S-sulfhydrated H3 (sJournal of assisted reproduction and geneticsA novel posttranslational modification of histone, H3 S-sulfhydration, is down-regulated in asthenozoospermic sperm.PMC866641120194Y023721140903600815714958197144321S11901000Pan HZhang FDiao HSun SZhang MWan XZhang LLi RJiang NWang JQi QfalseA novel posttranslational modification of histone, H3 S-sulfhydration, is down-regulated in asthenozoospermic sperm.Oxidative stress is one of the major causes leading to male infertility including asthenozoospermia. Hydrogen sulfide (H₂S) has been widely recognized to be a potent antioxidant whose role is partially implemented by protein S-sulfhydration. However, protein S-sulfhydration has not been reported in germ cells. Therefore, we investigated whether asthenozoospermia could be associated with sperm protein S-sulfhydration. S-sulfhydrated proteins in human sperm were enriched via biotin-switch assay and analyzed using LC-MS/MS spectrometry. Two hundred forty-four S-sulfhydrated proteins were identified. Importantly, we validated that sperm histones H3.1 and H3.3 were the S-sulfhydrated proteins. Their S-sulfhydrated amino acid residue was Cysteine111. Abundances of S-sulfhydrated H3 (s2021-01-01T00:00:00Z2021 Dec2026-04-08T17:54:20.543Z2025-04-05T15:23:23.49ZS-EPMC86664113466418410.1007/s10815-021-02314-x