Recent bioinformatic analyses have found repeating elements,
termed Clustered Repeating Interspersed Short Palindromic
Repeats or CRISPRs, in nearly half of all sequenced bacterial
genomes and all but one sequenced archaeal genome. These repeats
consist of a single unit made up of a repeat (30-60nt) and a
unique spacer (30-60nt). CRISPR loci contain between 4 and 100
units and organisms may have several CRISPR loci within their
genome. Further sequence analysis has shown that many of the
spacer sequences match with 100% sequence identity to the genomes
of phage known to infect the particular prokaryote. It has been
hypothesized that these CRISPRs function as a type of prokaryotic
immune system, perhaps in a method analogous to eukaryotic
RNA interference (RNAi). I am interested in characterizing
the two CRISPRs and the CRISPR associated (cas) proteins in
Pseudomonas aeruginosa. I am currently characterizing the
expression profile of the predicted cas proteins and the CRISPRs.
