Influence of specific growth rate and nutrient-limitation upon the sensitivity of Escherichia coli towards polymyxin B.
The sensitivity of Escherichia coli to the lytic action of polymyxin B was assessed for cells grown in a chemostat at a variety of specific growth rates and under conditions of carbon, nitrogen, phosphorus and magnesium limitation. Magnesium and phosphorus limited cells demonstrated a trend of increased resistance with increasing growth-rate, whereas carbon and nitrogen limited cells increased their sensitivity as the growth rate increased. Divergent patterns of sensitivity, such as these, allowed a number of models for resistance towards polymyxin to be assessed. It was not possible to attribute polymyxin sensitivity to any single envelope component; rather the patterns of sensitivity reflect, in a complex manner, presence of envelope proteins and acidic phospholipids.
Wright
N E
NE
Department of Pharmacy, University of Manchester, UK.
Gilbert
P
P
D002244:Carbon / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development; D005453:Fluorescence; D050356:Lipid Metabolism; D008274:Magnesium / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D011112:Polymyxin B / Q000494:pharmacology*; D011113:Polymyxins / Q000494:pharmacology*
D011113:Polymyxins; D010758:Phosphorus; D002244:Carbon; D008274:Magnesium; D011112:Polymyxin B; D009584:Nitrogen