the derived amino acid sequence exhibits homology ( 40 % ) with the sequence of the [ nife ] hydrogenase and the carboxy-terminus of the gene for the large subunit contains a codon ( tga ) for selenocysteine in a position homologous to a codon ( tgc ) for cysteine in the large subunit of the [ nife ] hydrogenase .
C0074289
selenocysteine
C0010654
cysteine