Protein
Protein-methionine-sulfoxide reductase heme-binding subunit MsrQ
Organism
Escherichia coli O6:H1 (strain CFT073 / ATCC 700928 / UPEC)
Function
Part of the MsrPQ system that repairs oxidized periplasmic proteins containing methionine sulfoxide residues (Met-O), using respiratory chain electrons. Thus protects these proteins from oxidative-stress damage caused by reactive species of oxygen and chlorine generated by the host defense mechanisms. MsrPQ is essential for the maintenance of envelope integrity under bleach stress, rescuing a wide series of structurally unrelated periplasmic proteins from methionine oxidation, including the primary periplasmic chaperone SurA and the lipoprotein Pal. MsrQ provides electrons for reduction to the reductase catalytic subunit MsrP, using the quinone pool of the respiratory chain.
Similarity
Belongs to the MsrQ family.
Sequence
MRLTAKQVTWLKVCLHLAGLLPFLWLVWAINHGGLGADPVKDIQHFTGRTALKFLLAALLITPLARYAKQPLLIRTRRLLGLWCFAWATLHLTSYALLELGVNNLALLGKELITRPYLTLGIISWVILLALAFTSTQSMQRKLGKHWQQLHNFVYLVAILAPIHYLWSVKIISPQPLIYAGLAVLLLALRYKKLLSLFNRLRKQAHNKLSL