Protein
Heme chaperone HemW
Organism
Lactococcus lactis subsp. lactis (strain IL1403)
Function
Could serve in the delivery of heme to a membrane-localized target protein (Probable). Binds one molecule of heme per monomer, possibly covalently; heme and Fe-S cluster binding are independent. Incubation with the reductant sodium dithionite increases binding. Does not have coproporphyrinogen III dehydrogenase activity in vitro, does not complement an E.coli hemN deletion in vivo (PubMed:22142238). Binds 1 Fe-S cluster, it is probably [4Fe-4S]. The cluster is coordinated with 3 cysteines and an exchangeable S-adenosyl-L-methionine; only dimeric protein has the cluster (Probable).
Similarity
Belongs to the anaerobic coproporphyrinogen-III oxidase family. HemW subfamily.
Sequence
MLQKPNSAYFHIPFCSHICYYCDFAKVLMTGQPIDAYIESLIEEFQSFEIEKLRTIYIGGGTPSVLSAQQLERLLTAIAEQLDLEVLEEFTVEANPGDLSDEVIKVLADSAVNRISLGVQTFNNALLKKIGRTHTEVQVYDSVERLKKAGFENITIDLIYALPGQTMEMVKSDVEKFLELKLPHVALYSLILEDHTVFMNRQRRGLLRLPSEDKNADMYEYIMDILAKNGYNHYEVSNFGLPGFESKHNITYWDNEEYYGIGAGASGYLAGIRYKNLGPVHHYLKAAPTEKRINEEVLSKKSQIEEEMFLGLRKKSGVLVEKFENKFKCSFEKLYGEQITELINQKLLYNDRQRIHMTDKGFELGNNVFEKFLLDDINF