Characterization of heteropolymeric hexosaminidase A in human X mouse hybrid cells.

Abstract
Expression of heteropolymeric hexosaminidase A activity is reported in a human .times. mouse hybrid cell line that contains an X/15 translocation chromosome but lacks human chromosome 5 and has no detectable human hexosaminidase B activity. (Hexosaminidase is .beta.-N-acetylglucosaminidase; EC 3.2.1.30; 2-acetamido-2-deoxy-.beta.-D-glucoside acetamidodeoxyglucohydrolase.) That the hexosaminidase A enzyme of these cells contains the human hexosaminidase-.alpha. subunit and not the human hexosaminidase-.beta. subunit is indicated by the cells'' reactions to specific antisera prepared against the .alpha. subunit and against the .beta. subunit. The hexosaminidase A activity in this hybrid cell line is the expression of a hybrid molecule composed of human hexosaminidase-.alpha. subunit and a mouse hexosaminidase subunit. The human hexosaminidase A enzyme may be formed from .alpha. and .beta. subunits coded for by genes on chromosomes 15 and 5, respectively.