Download MendeleyStructural insight into the carboxylesterase BioH from Klebsiella pneumoniae.
Wang, L., Chen, Y., Shang, F., Liu, W., Lan, J., Gao, P., Ha, N.C., Nam, K.H., Dong, Y., Quan, C., Xu, Y.(2019) Biochem Biophys Res Commun 520: 538-543
- PubMed: 31615653
- DOI: https://doi.org/10.1016/j.bbrc.2019.10.050
- Primary Citation of Related Structures:
6K5E - PubMed Abstract:
The BioH carboxylesterase which is a typical α/β-hydrolase enzyme involved in biotin synthetic pathway in most bacteria. BioH acts as a gatekeeper and blocks the further elongation of its substrate. In the pathogen Klebsiella pneumoniae, BioH plays a critical role in the biosynthesis of biotin. To better understand the molecular function of BioH, we determined the crystal structure of BioH from K. pneumoniae at 2.26 Å resolution using X-ray crystallography. The structure of KpBioH consists of an α-β-α sandwich domain and a cap domain. B-factor analysis revealed that the α-β-α sandwich domain is a rigid structure, while the loops in the cap domain shows the structural flexibility. The active site of KpBioH contains the catalytic triad (Ser82-Asp207-His235) on the interface of the α-β-α sandwich domain, which is surrounded by the cap domain. Size exclusion chromatography shows that KpBioH prefers the monomeric state in solution, whereas two-fold symmetric dimeric formation of KpBioH was observed in the asymmetric unit, the conserved Cys31-based disulfide bonds can maintain the irreversible dimeric formation of KpBioH. Our study provides important structural insight for understanding the molecular mechanisms of KpBioH and its homologous proteins.
Organizational Affiliation:
School of Life Science and Biotechnology, Dalian University of Technology, No 2 Linggong Road, Dalian, 116024, Liaoning, China; Department of Bioengineering, College of Life Science, Dalian Minzu University, Dalian, 116600, Liaoning, China; Key Laboratory of Biotechnology and Bioresources Utilization (Dalian Minzu University), Ministry of Education, China.
