Isolation and characterization of an extracellular haem‐binding protein from Pseudomonas aeruginosa that shares function and sequence similarities with the Serratia marcescens HasA haemophore

作者：Sylvie Létoffé, Virginie Redeker, Cécile Wandersman · 发表于：Molecular Microbiology · 年份：1998 · DOI：10.1046/j.1365-2958.1998.00885.x · 被引用次数：166 · 研究领域：Iron Metabolism and Disorders、Hemoglobin structure and function、Antibiotic Resistance in Bacteria

The major mechanism by which bacteria acquire free or haemoglobin-bound haem involves direct binding to specific outer membrane receptors. Serratia marcescens also secretes a haem-binding protein, HasA, which functions as a haemophore that catches haem and shuttles it to a cell surface specific outer membrane receptor, HasR. We report the isolation and characterization of hasAp, a gene from Pseudomonas aeruginosa. HasAp is an iron-regulated extracellular haem-binding protein that shares about 50% identity with HasA. HasAp is required for P. aeruginosa utilization of haemoglobin iron. It can replace HasA for HasR-dependent haemoblobin acquisition in a system reconstituted in Escherichia coli. HasAp, like HasA, lacks a signal peptide and is secreted by an ABC transporter. These findings show that haemophore-dependent haem acquisition is not unique to S. marcescens.