Structural characterization of Helicobacterpylori dethiobiotin synthetase reveals differences between family members

• Published in: The FEBS journal Vol. 279; no. 6; pp. 1093 - 1105
• Main Authors: Porebski, Przemyslaw J, Klimecka, Maria, Chruszcz, Maksymilian, Nicholls, Robert A, Murzyn, Krzysztof, Cuff, Marianne E, Xu, Xiaohui, Cymborowski, Marcin, Murshudov, Garib N, Savchenko, Alexei, Edwards, Aled, Minor, Wladek
• Format: Journal Article
• Language: English
• Published: Oxford Blackwell Publishing Ltd 01-03-2012
• Subjects: Bacteria; Biochemistry; Biosynthesis; Enzymes; Protein synthesis
• ISSN: 1742-464X; 1742-4658
• DOI: 10.1111/j.1742-4658.2012.08506.x

Dethiobiotin synthetase (DTBS) is involved in the biosynthesis of biotin in bacteria, fungi, and plants. As humans lack this pathway, DTBS is a promising antimicrobial drug target. We determined structures of DTBS from Helicobacterpylori (hpDTBS) bound with cofactors and a substrate analog, and described its unique characteristics relative to other DTBS proteins. Comparison with bacterial DTBS orthologs revealed considerable structural differences in nucleotide recognition. The C-terminal region of DTBS proteins, which contains two nucleotide-recognition motifs, differs greatly among DTBS proteins from different species. The structure of hpDTBS revealed that this protein is unique and does not contain a C-terminal region containing one of the motifs. The single nucleotide-binding motif in hpDTBS is similar to its counterpart in GTPases; however, isothermal titration calorimetry binding studies showed that hpDTBS has a strong preference for ATP. The structural determinants of ATP specificity were assessed with X-ray crystallographic studies of hpDTBS·ATP and hpDTBS·GTP complexes. The unique mode of nucleotide recognition in hpDTBS makes this protein a good target for H.pylori-specific inhibitors of the biotin synthesis pathway. [PUBLICATION ABSTRACT]