Bovine seminal plasma ASFP: Localization of disulfide bridges and detection of three different isoelectric forms

FEBS Letters

Töfper-Petersen, Edda²  Calvete, Juan J.²  Krause, Ingolf¹  Einspanier, Ralf³  Karg, Heinrich³  Klostermeyer, Henning¹ 

[1] Institut für Chemie und Physik, Forschungszentrum für Milch und Lebensmittel- Weihenstephan, Freising, Germany;Institut für Reproduktionsmedizin, Tierärztliche Hochschule, Hannover, Germany;Institut für Physiologie and Institut für Chemie und Physik, Forschungszentrum für Milch und Lebensmittel-Weihenstephan, Freising, Germany

关键词: Bovine seminal plasma;    aSFP;    Isoelectric focusing;    Disulfide bridges;    CUB domain;   

DOI  :  10.1016/0014-5793(94)00362-9

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Acidic seminal fluid protein (aSFP) is a major 13 kDa protein isolated from bull seminal plasma and characterized as a new growth factor which stimulates in vitro cell division and progesterone secretion by ovarian cells. Here, we establish that the four cysteines of oxidized aSFP form two disulfide bridges between nearest-neighbour residues. This pattern is conserved in boar spermadhesins, with which aSFP shares up to 50% amino acid sequence identity, and other proteins of the recently identified CUB domain family. Using isoelectric focusing in combination with sulfhydryl group-specific blotting, the three forms of aSFP were identified as completely oxidized (pI 4.7), partly reduced (pI 4.8) and fully reduced at pI 5.1. These results indicate that native aSFP possesses two pairs of cysteine residues of different reactivity. The observation that aSFP can protect sperm from oxidative damage might be explained by its reduction/oxidation behaviour.

【 授权许可】

Unknown