2BOZ

Photosynthetic Reaction Center Mutant With Gly M203 Replaced With Leu

Summary for 2BOZ

• Entry DOI: 10.2210/pdb2boz/pdb
• Related: 1AIG 1AIJ 1DS8 1DV3 1DV6 1E14 1E6D 1F6N 1FNP 1FNQ 1JGW 1JGX 1JGY 1JGZ 1JH0 1K6L 1K6N 1KBY 1L9B 1L9J 1M3X 1MPS 1OGV 1PCR 1PSS 1PST 1QOV 1RG5 1RGN 1RQK 1RVJ 1RY5 1RZH 1RZZ 1S00 1UMX 1YST 2BFJ 2BFS 2BFT 2BNP 2BNS 2RCR 4RCR
• Descriptor: REACTION CENTER PROTEIN H CHAIN, PHOSPHATE ION, SPEROIDENONE, ... (12 entities in total)
• Functional Keywords: photosynthesis, cardiolipin, electron transport, membrane protein, reaction center
• Biological source: RHODOBACTER SPHAEROIDES; More
• Cellular location: Cellular chromatophore membrane; Single-pass membrane protein: P11846; Cellular chromatophore membrane; Multi-pass membrane protein: P02954 P02953
• Total number of polymer chains: 3
• Total formula weight: 103203.72

Authors

Potter, J.P.,Fyfe, P.K.,Jones, M.R. (deposition date: 2005-04-15, release date: 2005-05-20, Last modification date: 2024-05-01)

Primary citation

Potter, J.A.,Fyfe, P.K.,Frolov, D.,Wakeham, M.C.,Van Grondelle, R.,Robert, B.,Jones, M.R.
Strong Effects of an Individual Water Molecule on the Rate of Light-Driven Charge Separation in the Rhodobacter Sphaeroides Reaction Center.
J.Biol.Chem., 280:27155-, 2005

PubMed Abstract: The role of a water molecule (water A) located between the primary electron donor (P) and first electron acceptor bacteriochlorophyll (B(A)) in the purple bacterial reaction center was investigated by mutation of glycine M203 to leucine (GM203L). The x-ray crystal structure of the GM203L reaction center shows that the new leucine residue packs in such a way that water A is sterically excluded from the complex, but the structure of the protein-cofactor system around the mutation site is largely undisturbed. The results of absorbance and resonance Raman spectroscopy were consistent with either the removal of a hydrogen bond interaction between water A and the keto carbonyl group of B(A) or a change in the local electrostatic environment of this carbonyl group. Similarities in the spectroscopic properties and x-ray crystal structures of reaction centers with leucine and aspartic acid mutations at the M203 position suggested that the effects of a glycine to aspartic acid substitution at the M203 position can also be explained by steric exclusion of water A. In the GM203L mutant, loss of water A was accompanied by an approximately 8-fold slowing of the rate of decay of the primary donor excited state, indicating that the presence of water A is important for optimization of the rate of primary electron transfer. Possible functions of this water molecule are discussed, including a switching role in which the redox potential of the B(A) acceptor is rapidly modulated in response to oxidation of the primary electron donor.

PubMed: 15908429
DOI: 10.1074/JBC.M501961200

Experimental method

X-RAY DIFFRACTION (2.4 Å)