    6.3.1.21 | dimer |
the A-domain is formed by segment Thr2-Ala122 and is dominated by a five-stranded parallel beta-pleated sheet flanked on either side by two alpha-helices. The smallest of the three structural motifs of the PurT transformylase, the B-domain is formed by Glu123-Gly196 and contains a four-stranded antiparallel beta-sheet with the strands ranging in length from three to five amino acid residues. The most complicated of the domains, the C-motif extends from Val197 to Gly392 and is composed primarily of an eight-stranded antiparallel beta-pleated sheet formed by Phe202-Ser210, Val215-Gln225, Tyr230-Gln235, Gly262-Val270, Val275-Ser281, Ala321-Ile326, Gln349-Leu352, and Gly365-Thr370. There are two additional regions of antiparallel beta-sheet formed by Gln329-Ser332 and Ile358-Ser361 and Thr336-Asp338 and Val388-Gly392, respectively. The four alpha-helices located in the C-domain range in length from four to eighteen amino acid residues. There are seven classical reverse turns in the C-domain that link these various beta-strands and alpha-helices together (three type I, one type I', one type II, one type II', and one type III). The dimeric interface is formed from regions provided by both the A- and C-domains. Enzyme structure analysis, detailed overview |
760559 |
