Open AccessStructure of putative 4‐amino‐4‐deoxychorismate lyase from Thermus thermophilus HB8
Author(s) -
Padmanabhan Balasundaram,
Bessho Yoshitaka,
Ebihara Akio,
Antonyuk Svetlana V.,
Ellis Mark J.,
Strange Richard W.,
Kuramitsu Seiki,
Watanabe Nobuhisa,
Hasnain S. Samar,
Yokoyama Shigeyuki
Publication year - 2009
Publication title -
acta crystallographica section f
Language(s) - English
Resource type - Journals
ISSN - 1744-3091
DOI - 10.1107/s1744309109050052
Subject(s) - thermus thermophilus , lyase , pyridoxal phosphate , pyridoxal , biochemistry , active site , enzyme , cofactor , amino acid , chemistry , stereochemistry , escherichia coli , biology , gene
The pyridoxal 5′‐phosphate‐dependent enzyme 4‐amino‐4‐deoxychorismate lyase converts 4‐amino‐4‐deoxychorismate to p ‐aminobenzoate and pyruvate in one of the crucial steps in the folate‐biosynthesis pathway. The primary structure of the hypothetical protein TTHA0621 from Thermus thermophilus HB8 suggests that TTHA0621 is a putative 4‐amino‐4‐deoxychorismate lyase. Here, the crystal structure of TTHA0621 is reported at 1.93 Å resolution. The asymmetric unit contained four NCS molecules related by 222 noncrystallographic symmetry, in which the formation of intact dimers may be functionally important. The cofactor pyridoxal 5′‐phosphate (PLP) binds to the protein in the large cleft formed by the N‐terminal and C‐terminal domains of TTHA0621. The high structural similarity and the conservation of the functional residues in the catalytic region compared with 4‐amino‐4‐deoxychorismate lyase (PabC; EC 4.1.3.38) from Escherichia coli suggest that the TTHA0621 protein may also possess 4‐amino‐4‐deoxychorismate lyase activity.