2p04

2.1 Ang structure of the dimerized PAS domain of signal transduction histidine kinase from Nostoc punctiforme PCC 73102 with homology to the H-NOXA/H-NOBA domain of the soluble guanylyl cyclase2.1 Ang structure of the dimerized PAS domain of signal transduction histidine kinase from Nostoc punctiforme PCC 73102 with homology to the H-NOXA/H-NOBA domain of the soluble guanylyl cyclase

Structural highlights 2p04 is a 2 chain structure with sequence from Nostoc punctiforme pcc 73102. The January 2011 RCSB PDB Molecule of the Month feature on Nitric Oxide Synthase by David Goodsell is 10.2210/rcsb_pdb/mom_2011_1. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Related: 2p08 Gene: COG0642 (Nostoc punctiforme PCC 73102) Resources: FirstGlance, OCA, RCSB, PDBsum Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed Signal transduction histidine kinases (STHK) are key for sensing environmental stresses, crucial for cell survival, and attain their sensing ability using small molecule binding domains. The N-terminal domain in an STHK from Nostoc punctiforme is of unknown function yet is homologous to the central region in soluble guanylyl cyclase (sGC), the main receptor for nitric oxide (NO). This domain is termed H-NOXA (or H-NOBA) because it is often associated with the heme-nitric oxide/oxygen binding (H-NOX) domain. A structure-function approach was taken to investigate the role of H-NOXA in STHK and sGC. We report the 2.1 A resolution crystal structure of the dimerized H-NOXA domain of STHK, which reveals a Per-Arnt-Sim (PAS) fold. The H-NOXA monomers dimerize in a parallel arrangement juxtaposing their N-terminal helices and preceding residues. Such PAS dimerization is similar to that previously observed for EcDOS, AvNifL, and RmFixL. Deletion of 7 N-terminal residues affected dimer organization. Alanine scanning mutagenesis in sGC indicates that the H-NOXA domains of sGC could adopt a similar dimer organization. Although most putative interface mutations did decrease sGCbeta1 H-NOXA homodimerization, heterodimerization of full-length heterodimeric sGC was mostly unaffected, likely due to the additional dimerization contacts of sGC in the coiled-coil and catalytic domains. Exceptions are mutations sGCalpha1 F285A and sGCbeta1 F217A, which each caused a drastic drop in NO stimulated activity, and mutations sGCalpha1 Q368A and sGCbeta1 Q309A, which resulted in both a complete lack of activity and heterodimerization. Our structural and mutational results provide new insights into sGC and STHK dimerization and overall architecture. PAS-mediated dimerization of soluble guanylyl cyclase revealed by signal transduction histidine kinase domain crystal structure.,Ma X, Sayed N, Baskaran P, Beuve A, van den Akker F J Biol Chem. 2008 Jan 11;283(2):1167-78. Epub 2007 Nov 15. PMID:18006497 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 2p04, resolution 2.11Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image