Overexpression in Escherichia coli and functional reconstitution of the liposome binding ferriheme protein nitrophorin 7 from the bloodsucking bug Rhodnius prolixus.

ABSTRACT: A number of ferriheme proteins, termed nitrophorins (NPs), occur in the saliva of the bloodsucking insect Rhodnius prolixus ('kissing bug'), which is a vector for Chagas' disease. Nitrophorins bind the heme b cofactor in the beta-barrel of their lipocalin fold, which is further anchored through a proximal histidine-Fe(III) bond. The distal Fe(III) coordination site then binds nitric oxide (NO) for delivery into a host's tissues during blood feeding, where, upon NO release, the distal Fe(III) site acts as a histamine trap to delay the victim's immune response. Previously, four nitrophorins from R. prolixus, NP1 to NP4, have been extensively characterized. Recently, another nitrophorin, NP7, was discovered in a cDNA library derived from the same insect. Among the R. prolixus nitrophorins, NP

SUBMITTER: Knipp M 

PROVIDER: S-EPMC2094717 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature