Alignment of the p110 amino acid sequence with the N. crassa (29) mitochondrial GDH sequence. The sequences were aligned by the GCG BESTFIT local alignment program; the p110 sequence is above and the N. crassa sequence below. Gaps are indicated by dashes, identical amino acids by bars, and conservative amino acid substitutions by one or two dots. Stars indicate conserved residues found in both hexameric and tetrameric glutamate dehydrogenases (8), and the consensus sequence for the dinucleotide-binding domain is underlined. The N-terminal sequence of the mature p110 protein (ASSNATSPPVSLDAIV) is boxed, as are the sequences of the two tryptic peptides pp59A (IIVEGANLFISQDA) and pp59B (LEFNAI) which were used to construct degenerate oligonucleotides for PCR. The fragment corresponding to the 327 amino acids expressed in E. coli as a fusion protein is demarcated by two lines. The N-terminal five amino acids of the p110 sequence are not shown since they do not align with the N. crassa sequence; they are MMRHT.