Utilization of hemin and hemoglobin as iron sources by Vibrio parahaemolyticus and identification of an iron-repressible hemin-binding protein.
Several clinical isolates of Vibrio parahaemolyticus were examined for their ability to utilize either hemin or hemoglobin as a sole source of iron. Both compounds appeared to be equally good iron sources. Maximum growth was obtained at 5 microM hemin or 1.25 microM hemoglobin under the conditions tested. Using a hemin-agarose batch affinity method, the hemin-binding protein was isolated from crude total membranes of a hemin-utilizing strain, WP1, grown under iron-deficient but not under iron-sufficient conditions. This protein was identical to the 83 kDa outer membrane protein which was expressed in response to iron limitation. The protein was susceptible to proteinase K cleavage in whole cells, indicating its exposure at the cell surface. Hemin and hemoglobin, but not protoporphyrin IX, inhibited binding of the protein to hemin-agarose.
Yamamoto
S
S
Faculty of Pharmaceutical Sciences, Okayama University, Japan.
Hara
Y
Y
Tomochika
K
K
Shinoda
S
S
D002352:Carrier Proteins / Q000302:isolation & purification* / Q000378:metabolism; D000081062:Heme-Binding Proteins; D006420:Hemeproteins / Q000302:isolation & purification* / Q000378:metabolism; D006427:Hemin / Q000378:metabolism* / Q000494:pharmacology; D006454:Hemoglobins / Q000378:metabolism* / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D014736:Vibrio parahaemolyticus / Q000737:chemistry / Q000254:growth & development / Q000378:metabolism*
D002352:Carrier Proteins; D000081062:Heme-Binding Proteins; D006420:Hemeproteins; D006454:Hemoglobins; D006427:Hemin