5hbc

Intermediate structure of iron-saturated C-lobe of bovine lactoferrin at 2.79 Angstrom resolution indicates the softening of iron coordination

spinqualitylabelsall models 5hbc, resolution 2.79Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5hbc is a 2 chain structure with sequence from Bos taurus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: BCT, BMA, FE, NAG Related: 4oqo Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [TRFL_BOVIN] Transferrins are iron binding transport proteins which can bind two Fe(3+) ions in association with the binding of an anion, usually bicarbonate. Lactotransferrin has antimicrobial activity. The most effective inhibitory activity was seen against E.coli and P.aeruginosa. Lactoferricin B is an antimicrobial peptide. Inhibits the growth of Gram-negative and Gram-positive bacteria. The lactotransferrin transferrin-like domain 1 functions as a serine protease of the peptidase S60 family that cuts arginine rich regions. This function contributes to the antimicrobial activity. Publication Abstract from PubMed The bilobal lactoferrin is an approximately 76 kDa glycoprotein. It sequesters two Fe(3+) ions together with two CO32- ions. The C-terminal half (residues, Tyr342-Arg689, C-lobe) of bovine lactoferrin (BLF) (residues Ala1-Arg689) was prepared by limited proteolysis using trypsin. Both C-lobe and intact BLF were saturated to 100%. Both of them retained up to nearly 85% of iron at pH 6.5. At pH 5.0, C-lobe retained 75% of iron whereas intact protein could retain only slightly more than 60%. At pH 4.0 both contained 25% iron and at pH 2.0 they were left with iron concentration of only 10%. The structure of iron saturated C-lobe was determined at 2.79 A resolution and refined to Rcryst and Rfree factors of 0.205 and 0.273, respectively. The structure contains two crystallographically independent molecules, A and B. They were found to have identical structures with an r.m.s. shift of 0.5 A for their C(alpha) atoms. A high solvent content of 66% was observed in the crystals. The average value of an overall B-factor was 68.0 A(2) . The distance of 2.9 A observed for the coordination bond between Fe(3+) ion and N(e2) of His595 appeared to be considerably longer than the normally observed values of 1.9-2.2 A. This indicated that the coordination bond involving His595 may be absent. Other coordination distances were observed in the range of 2.1-2.3 A. Based on the present structure of iron saturated C-lobe, it may be stated that His595 is the first residue to dissociate from ferric ion when the pH is lowered. Proteins 2016; 84:591-599. (c) 2016 Wiley Periodicals, Inc. Structure of iron saturated C-lobe of bovine lactoferrin at pH 6.8 indicates a weakening of iron coordination.,Rastogi N, Singh A, Singh PK, Tyagi TK, Pandey S, Shin K, Kaur P, Sharma S, Singh TP Proteins. 2016 May;84(5):591-9. doi: 10.1002/prot.25004. Epub 2016 Feb 24. PMID:26850578 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA