DETERMINATION OF GENOME SIZE OF PSEUDOMONAS-AERUGINOSA BY PFGE - ANALYSIS OF RESTRICTION FRAGMENTS

Genomic DNA size was measured in three strains of Pseudomonas aeruginosa, ATCC 29260 (exotoxin A), ATCC 33467 (type I smooth) and ATCC 33468 (type 2 mucoid) by transverse alternating field electrophoresls of restriction fragments. Because of the high (67%) G + C content of Pseudomonas aeruginosa, restriction enzymes that recognize sequences with at least 4 AT base pairs were expected to be rare cutters. Eight enzymes produced fragments greater than 200 kb in size: Dral (TTT/AAA), Asnl (ATT/AAT), Hpal (GTT/AAC), Aflll (C/TTAAG), Xbal (T/CTAGA), Spel (A/CTAGT), Sspl (AAT/ATT) and Ndel (CA/TATG). All eight enzymes recognized one of three rare etranucleotide sequences, TTAA, CTAG or ATAT. Pseudomonas aeruginosa strain 29260 has a genomic ONA size of 5573 kb. Strains 33467 and 33468 have identical restriction patterns and a possible deletion with a genomic size of 5407 kb. © 1990 Oxford University Press.