Mutational analyses reveal overall topology and functional regions of NilB, a bacterial outer membrane protein required for host association in a model of animal-microbe mutualism.

ABSTRACT: The gammaproteobacterium Xenorhabdus nematophila is a mutualistic symbiont that colonizes the intestine of the nematode Steinernema carpocapsae. nilB (nematode intestine localization) is essential for X. nematophila colonization of nematodes and is predicted to encode an integral outer membrane beta-barrel protein, but evidence supporting this prediction has not been reported. The function of NilB is not known, but when expressed with two other factors encoded by nilA and nilC, it confers upon noncognate Xenorhabdus spp. the ability to colonize S. carpocapsae nematodes. We present evidence that NilB is a surface-exposed outer membrane protein whose expression is repressed by NilR and growth in nutrient-rich medium. Bioinformatic analyses reveal that NilB is the only characterized member of

SUBMITTER: Bhasin A 

PROVIDER: S-EPMC3302474 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature