PLASMID PROFILES, ADHESIVE AND INVASIVE PROPERTIES OF SALMONELLA SER TYPHIMURIUM STRAINS - PHAGE TYPE-99 AND TYPE-36

Adhesive and invasive properties were compared with plasmid profile in S. Typhimurium strains of phage type 99(10) and 36(10). All strains o f phage type 99 were multiple drug resistant (ApCmKmSmSuTcTp) and harb oured small plasmids of 2.4 - 5.2 MDal. Six strains of the phage type 36 had ApCmTc R-pattern and two with only ampicillin resistance, carri ed plasmids of molecular size 2.6-5.2 MDal; two strains were sensitive to all antibiotics and devoid of plasmids. None of the strains were f ound to harbour high molecular weight plasmids. All plasmid positive s trains of phage types 99 and 36 could be divided into two groups of th ree plasmid patterns each, which were phage type specific. All plasmid positive and negative strains adhered and invaded HeLa cells to diffe rent degrees. No correlation could be established between plasmid prof ile and adhesion invasion characteristics. High molecular weight plasm ids therefore are unlikely to be essential for adhesion and invasion.