Structure of inorganic pyrophosphatase from Helicobacter pylori.
Inorganic pyrophosphatase (PPase) is a ubiquitous cytosolic enzyme which catalyzes the hydrolysis of inorganic pyrophosphate (PPi) to orthophosphate (Pi). The crystal structure of inorganic pyrophosphatase from Helicobacter pylori (H-PPase) has been solved by MAD and refined to an R factor of 20.6% at 2.6 A resolution. The crystallographic asymmetric unit contains a homohexameric H-PPase arranged as a dimer of trimers. While most of the structural elements of PPases are highly conserved in H-PPase, some unique structural features are localized in the flexible loops near the active site, suggesting that the structural flexibility of these loops is required for the catalytic efficiency of PPase.
Wu
Chun Ai
CA
Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon 440-746, South Korea.
Lokanath
Neratur K
NK
Kim
Dong Young
DY
Park
Hye Jin
HJ
Hwang
Hye Yeon
HY
Kim
Seong Tae
ST
Suh
Se Won
SW
Kim
Kyeong Kyu
KK
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005784:Gene Amplification; D016480:Helicobacter pylori / Q000201:enzymology* / Q000235:genetics; D043564:Inorganic Pyrophosphatase / Q000737:chemistry* / Q000235:genetics; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D011487:Protein Conformation; D016415:Sequence Alignment
D001426:Bacterial Proteins; D043564:Inorganic Pyrophosphatase