Identification of low-molecular-weight compounds in goat epididymis using multinuclear nuclear magnetic resonance

Multinuclear nuclear magnetic resonance (NMR) (H-1, C-13, and P-31) studies have been performed on aqueous solutions of lyophilysates of cell-free ext ract, epididymal fluid, and intact cells from caput and cauda regions of ep ididymis of sacrificed goats. Identification of low-molecular-weight compou nds present in different maturation phases of spermatozoa has been carried out. Several low-molecular-weight compounds have been identified by assigni ng 600 MHz H-1 NMR spectra with the help of two-dimensional homonuclear and heteronuclear correlation spectroscopy such as double quantum filtered cor relation spectroscopy and heteronuclear single quantum correlation spectros copy. Homonuclear coupling constants have also been used to get unambiguous assignments of resonances. NMR data were compared with those of standard s amples measured at same pH and with those reported in the literature. Ident ification of several amino acids, carbohydrates, and lipids have been made and their presence has been discussed in relation to their relevance to spe rm functions. The presence of beta-alanine and hypotaurine has been reporte d for the first time in goat epididymis. (C) 1999 Academic Press.