BMB170a_2011_LECTURE8

BMB170a_2011_LECTURE8 - BMB/Bi/Ch170a,Proteins,...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Metalloproteins Enzymes Nucleo4de binding proteins BMB/Bi/Ch170a Proteins Lecture 8, Oct 20
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Metalloproteins Es4mated ~1/3 of all proteins contain metals Na, Mg, K, Ca V, Mn, Fe, Co, Ni, Cu, Zn Mo, Cd, W Metalloproteomics: Structural and func4onal annota4on of proteins in structural genomics Shi et al Structure (2005)13:1±73 10²15% contain stoichiometric amounts of transi4on metals
Background image of page 2
Role of metals in basic geobiochemical cycles (2003) 300:942 N cycle K, Mg 10 8 atoms/cell ~10 mM Ca, Zn, Fe 10 5 atoms/cell~ 0.1 mM Cu, Mn, Mo 10 4 atoms/cell~ 10 µM V, Co, Ni low abundance (2003) 300:931 in vivo metal concentra±ons (E. coli)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Protein ligands Major ligands Cys, His, Asp, Glu Rarer examples Met (cytochrome c, azurin) Tyr (dioxygenase, catalase) Asn (Ca binding proteins, lipoxygenase) Gln (sub4lisin Ca, stellacyanin?) Ser (MoFe±protein, ferredoxins, DMSO reductase) Lys (phosphoenolpyruvate carboxykinase) carbonyl O (Ca 2+ sites) amide N (P cluster/nitrile hydratase) amino N (cytochrome f, CooA (pro)) carboxy C (lipoxygenase), formyl Met (Mg of Bchl in LH2) Arg (bio4n synthase) Trp? no examples yet ; Trp as radical ± cytc peroxidase
Background image of page 4
tetrahedral octahedral trigonal bipyramid square planar Idealized coordina4on geometries Typical metalSligand distances for Frst row metals: M S O/N 2.0S2.1 Å M S ± 2.3 Å His/Glu/Asp coord HN N N ε 2 N δ 1 HN N M M H preferred monoprotonated preferred in proteins (75%) preferred in peptides C O O C O O anti syn bidentate -1 -1 ±mallest coordina4on mo4fs 3 res S sq planar S AScluster Carbon monoxide dehydrogenaseSaCoA (1mjg) 6 res S sq planar S Nitrile hydratase 1² res S TetrS some Zn Fngers 12 res S Oct S calcium sites Harding Acta Cryst (2006) D62:678
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
distribu4on of Zn S N His in high resolu4on protein structures (res < 1.6 Å), rela4ve to d = 2.00 Å observed in small molecule structures Zn S O distances in PDB structures with bidentate carboxylate ligands (both d < 3.00 Å) Distribu4on of metal ligand distances in protein structures Harding Acta Cryst (2006) D62:678
Background image of page 6
2+ ? 2.78 2.11 2.12 2.12, 2.13 W 2.39 2.29 Aldehyde ferredoxin oxidoreductase Chan et al Science (1995) 267:1463 (1aor) Common components in protein solu±ons ² oOen at high conc Ion M••³ (Å) ion rad (Å) Favored coord num. Na + 2.42 0.95 6 Mg 2+ 2.07 0.65 6 K + 2.84 1.33 7²8 Ca 2+ 2.39 0.99 6²8 H 2 ³ ~2.8 4 Dis±nguishing Na + , Mg 2+ , K + , ( Ca 2+ ) from H 2 ³ ? Harding Acta
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/03/2012 for the course BI 170a taught by Professor List during the Fall '09 term at Caltech.

Page1 / 52

BMB170a_2011_LECTURE8 - BMB/Bi/Ch170a,Proteins,...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online