7C90

Crystal structure of Cytochrome CL from the marine methylotrophic bacterium Methylophaga aminisulfidivorans MPT (Ma-CytcL)

Summary for 7C90

• Entry DOI: 10.2210/pdb7c90/pdb
• Descriptor: Cytochrome c, mono-and diheme variant, HEME C, 4-(2-HYDROXYETHYL)-1-PIPERAZINE ETHANESULFONIC ACID, ... (8 entities in total)
• Functional Keywords: methanol oxidation system, marine bacterium, methylophaga aminisulfidivorans mpt, electron transport
• Biological source: Methylophaga aminisulfidivorans MP
• Total number of polymer chains: 4
• Total formula weight: 90756.96

Authors

Ghosh, S.,Dhanasingh, I.,Lee, S.H. (deposition date: 2020-06-04, release date: 2020-07-22, Last modification date: 2024-10-16)

Primary citation

Ghosh, S.,Dhanasingh, I.,Ryu, J.,Kim, S.W.,Lee, S.H.
Crystal Structure of CytochromecLfrom the Aquatic Methylotrophic BacteriumMethylophaga aminisulfidivoransMPT.
J Microbiol Biotechnol., 30:1261-1271, 2020

PubMed Abstract: Cytochrome (Cyt) is an essential protein in the process of methanol oxidation in methylotrophs. It receives an electron from the pyrroloquinoline quinone (PQQ) cofactor of methanol dehydrogenase (MDH) to produce formaldehyde. The direct electron transfer mechanism between Cyt and MDH remains unknown due to the lack of structural information. To help gain a better understanding of the mechanism, we determined the first crystal structure of heme c containing Cyt from the aquatic methylotrophic bacterium MP at 2.13 Å resolution. The crystal structure of -Cyt revealed its unique features compared to those of the terrestrial homologues. Apart from Fe in heme, three additional metal ion binding sites for Na , Ca , and Fe were found, wherein the ions mostly formed coordination bonds with the amino acid residues on the loop (G93-Y111) that interacts with heme. Therefore, these ions seemed to enhance the stability of heme insertion by increasing the loop's steadiness. The basic N-terminal end, together with helix α4 and loop (G126 to Y136), contributed positive charge to the region. In contrast, the acidic C-terminal end provided a negatively charged surface, yielding several electrostatic contact points with partner proteins for electron transfer. These exceptional features of -Cyt, along with the structural information of MDH, led us to hypothesize the need for an adapter protein bridging MDH to Cyt within appropriate proximity for electron transfer. With this knowledge in mind, the methanol oxidation complex reconstitution in vitro could be utilized to produce metabolic intermediates at the industry level.

PubMed: 32627749
DOI: 10.4014/jmb.2006.06029

Experimental method

X-RAY DIFFRACTION (2.13 Å)