PMID- 10608873
OWN - NLM
STAT- MEDLINE
DCOM- 20000208
LR  - 20210209
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 274
IP  - 53
DP  - 1999 Dec 31
TI  - Definition of the interaction domain for cytochrome c on cytochrome c oxidase. 
      Ii. Rapid kinetic analysis of electron transfer from cytochrome c to Rhodobacter 
      sphaeroides cytochrome oxidase surface mutants.
PG  - 38042-50
AB  - The reaction between cytochrome c (Cc) and Rhodobacter sphaeroides cytochrome c 
      oxidase (CcO) was studied using a cytochrome c derivative labeled with ruthenium 
      trisbipyridine at lysine 55 (Ru-55-Cc). Flash photolysis of a 1:1 complex between 
      Ru-55-Cc and CcO at low ionic strength results in electron transfer from 
      photoreduced heme c to Cu(A) with an intracomplex rate constant of k(a) = 4 x 
      10(4) s(-1), followed by electron transfer from Cu(A) to heme a with a rate 
      constant of k(b) = 9 x 10(4) s(-1). The effects of CcO surface mutations on the 
      kinetics follow the order D214N > E157Q > E148Q > D195N > D151N/E152Q 
      approximately D188N/E189Q approximately wild type, indicating that the acidic 
      residues Asp(214), Glu(157), Glu(148), and Asp(195) on subunit II interact 
      electrostatically with the lysines surrounding the heme crevice of Cc. Mutating 
      the highly conserved tryptophan residue, Trp(143), to Phe or Ala decreased the 
      intracomplex electron transfer rate constant k(a) by 450- and 1200-fold, 
      respectively, without affecting the dissociation constant K(D). It therefore 
      appears that the indole ring of Trp(143) mediates electron transfer from the heme 
      group of Cc to Cu(A). These results are consistent with steady-state kinetic 
      results (Zhen, Y., Hoganson, C. W., Babcock, G. T., and Ferguson-Miller, S. 
      (1999) J. Biol. Chem. 274, 38032-38041) and a computational docking analysis 
      (Roberts, V. A., and Pique, M. E. (1999) J. Biol. Chem. 274, 38051-38060).
FAU - Wang, K
AU  - Wang K
AD  - Department of Chemistry, University of Arkansas, Fayetteville, Arkansas 72701, 
      USA.
FAU - Zhen, Y
AU  - Zhen Y
FAU - Sadoski, R
AU  - Sadoski R
FAU - Grinnell, S
AU  - Grinnell S
FAU - Geren, L
AU  - Geren L
FAU - Ferguson-Miller, S
AU  - Ferguson-Miller S
FAU - Durham, B
AU  - Durham B
FAU - Millett, F
AU  - Millett F
LA  - eng
GR  - GM20488/GM/NIGMS NIH HHS/United States
GR  - GM26916/GM/NIGMS NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Cytochrome c Group)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
SB  - IM
MH  - Animals
MH  - Cytochrome c Group/*metabolism
MH  - Electron Transport
MH  - Electron Transport Complex IV/chemistry/genetics/*metabolism
MH  - Horses
MH  - Kinetics
MH  - Models, Molecular
MH  - Mutation
MH  - Osmolar Concentration
MH  - Rhodobacter sphaeroides/*enzymology
MH  - Ultracentrifugation
EDAT- 1999/12/23 00:00
MHDA- 1999/12/23 00:01
CRDT- 1999/12/23 00:00
PHST- 1999/12/23 00:00 [pubmed]
PHST- 1999/12/23 00:01 [medline]
PHST- 1999/12/23 00:00 [entrez]
AID - S0021-9258(19)52993-3 [pii]
AID - 10.1074/jbc.274.53.38042 [doi]
PST - ppublish
SO  - J Biol Chem. 1999 Dec 31;274(53):38042-50. doi: 10.1074/jbc.274.53.38042.