Comparison of the N-acetylhexosaminidase components in the ram testis and epididymis by isoelectric focusing.

1. Several enzymic components, with both N-acetyl-beta-glucosaminidase and N-acetyl-beta-galactosaminidase activity, have been demonstrated in the ram testis and epididymis by isoelectric focusing. 2. The component (I), which predominates in the testis and caput of the epididymis, is isoelectric at pH6.2+/-0.1, whereas the predominant component (II) in the epididymal isthmus and cauda is isoelectric at pH7.0+/-0.1. 3. The total activity and the relative proportions of the enzymic components vary in the different sections of the epididymis. 4. Although their pH optima are slightly different, the appropriate K(m) values for components I and II for the hydrolysis of 4-methylumbelliferyl-N-acetyl-beta-glucosaminide and N-acetyl-beta-galactosaminide and the ratios of the maximal velocities towards the two substrates are very similar.