krishnamurthy was the reader in botany from 1943 to 1960. in 1960 he joined thanjavur medical college as a professor of biology, and as professor of microbiology and bacteriology in the department of public health engineering in the college of engineering. in 1961 he joined central salts and marine chemicals research institute (csir), bhavnagar, gujarat as a scientist. after working in csir's laboratories for a decade (1961–1971) he returned to tamil nadu and served as professor of botany in various colleges. when he retired in 1979, he was principal at arignar anna government arts college for men namakkal.