PRODUCTION AND CHARACTERIZATION OF MONOCLONAL-ANTIBODIES TO BOVINE BRAIN SUCCINIC SEMIALDEHYDE REDUCTASE

Monoclonal antibodies against bovine brain succinic semialdehyde reduc tase were produced and characterized. A total of nine monoclonal antib odies recognizing different epitopes of the enzyme were obtained, of w hich two inhibited the enzyme activity and three stained cytosol of ra t spinal cord neurons as observed by indirect immunofluorescence micro scopy. When unfractionated total proteins of bovine brain homogenate w ere separated by gel electrophoresis and immunoblotted, the antibodies specifically recognized a single protein band of 34 kDa, which comigr ates with purified bovine succinic semialdehyde reductase. Using the a ntisuccinic semialdehyde reductase antibodies as probes, we investigat ed the cross-reactivities of brain succinic semialdehyde reductases fr om some mammalian and an avian species. The immunoreactive bands on we stern blots appeared to be the same in molecular mass-34 kDa-in all an imal species tested, including humans. The result indicates that brain succinic semialdehyde reductase is distinct from other aldehyde reduc tases and that mammalian brains contain only one succinic semialdehyde reductase. Moreover, the enzymes among the species are immunologicall y very similar, although some proper ties of the enzymes reported prev iously were different from one another.