1k1e
From Proteopedia
Structure Of the cobalt-bound form of the deoxy-D-mannose-octulosonate 8-phosphate phosphatase (YrbI) From Haemophilus Influenzae (HI1679)
Overview
The crystal structure of the YrbI protein from Haemophilus influenzae (HI1679) was determined at a 1.67-A resolution. The function of the protein had not been assigned previously, and it is annotated as hypothetical in sequence databases. The protein exhibits the alpha/beta-hydrolase fold (also termed the Rossmann fold) and resembles most closely the fold of the L-2-haloacid dehalogenase (HAD) superfamily. Following this observation, a detailed sequence analysis revealed remote homology to two members of the HAD superfamily, the P-domain of Ca(2+) ATPase and phosphoserine phosphatase. The 19-kDa chains of HI1679 form a tetramer both in solution and in the crystalline form. The four monomers are arranged in a ring such that four beta-hairpin loops, each inserted after the first beta-strand of the core alpha/beta-fold, form an eight-stranded barrel at the center of the assembly. Four active sites are located at the subunit interfaces. Each active site is occupied by a cobalt ion, a metal used for crystallization. The cobalt is octahedrally coordinated to two aspartate side-chains, a backbone oxygen, and three solvent molecules, indicating that the physiological metal may be magnesium. HI1679 hydrolyzes a number of phosphates, including 6-phosphogluconate and phosphotyrosine, suggesting that it functions as a phosphatase in vivo. The physiological substrate is yet to be identified; however the location of the gene on the yrb operon suggests involvement in sugar metabolism.
About this Structure
1K1E is a Single protein structure of sequence from Haemophilus influenzae. Full crystallographic information is available from OCA.
Reference
From structure to function: YrbI from Haemophilus influenzae (HI1679) is a phosphatase., Parsons JF, Lim K, Tempczyk A, Krajewski W, Eisenstein E, Herzberg O, Proteins. 2002 Mar 1;46(4):393-404. PMID:11835514 Page seeded by OCA on Fri May 2 22:10:45 2008
