Methods and compositions are provided for the production of human superoxide dismutase and a novel protocol for enhancing efficiency of expression. The gene encoding for human superoxide dismutase is isolated and inserted into a vector in conjunction with a synthetic linker which provides for enhanced efficiency in translation. E. coli strain D1210 (pSODX8) was deposited at the A.T.C.C. on Sep. 27, 1983 and given Accession No. 39453. Yeast strain 2150-2-3 (pC1/1GAPSOD) and E. coli strains D1210 (pSOD11) and D1210 (pS2OR) were deposited at the A.T.C.C. on May 9, 1984, and given Accession Nos. 20708, 39679 and 39,680, respectively.