pilO, a gene required for glycosylation of Pseudomonas aeruginosa 1244 pilin

Abstract

SUMMARYNucleotide sequencing of a region downstream from thePseudomonas aeruginosa1244 pilin structural gene,pilA, revealed an ORF potentially able to code for a protein ofMr50862. This ORF, calledpilO, was flanked by a tRNAthrgene, which was followed by a transcriptional termination sequence. The tRNAthrgene and the termination sequence were nearly identical to sequences found immediately adjacent to thepilAgene of severalP. aeruginosastrains. A 2200 base mRNA strand, which contained both thepilOandpilAtranscripts, was produced from this region, while a 650 base transcript containing onlypilAwas present in a 100-fold excess over the longer transcript. Hyperexpression of thepilAgene in a PilO-strain resulted in normal pilus-specific phage sensitivity and twitching motility. The pilin produced by this strain had a lower apparentMrand a more neutral pI compared to that produced by a strain containing a functionalpilOgene. This pilin failed to react with a sugar-specific reagent which recognized pilin produced by the strain containing a functionalpilOgene.