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Studies on antibiotic-resistant enterobacteria isolated from polluted river water

Hughes, Colin (1978) Studies on antibiotic-resistant enterobacteria isolated from polluted river water. Doctor of Philosophy (PhD) thesis, University of Kent. (doi:10.22024/UniKent/01.02.94429) (KAR id:94429)


Two methods were devised to simplify the examination of antibiotic-resistant enterobacteria from natural sources.

The efficient isolation of enterobacteria from polluted river water is allowed by supplementing bile salts medium with a critically small amount of nalidixic acid. This medium allows direct counting of coliforms by eliminating all other lactose fermenters.

A further procedure is described for demonstrating plasmid DNA and it's molecular weight, based on rate zonal centrifugation of unlabelled DNA in neutral sucrose gradients containing a low concentration of ethidium bromide. Each plasmid species, nicked during preparation of lysates, forms only a single band, thus simplifying the examination of plasmids from naturally occurring strains.

These methods were used to investigate standard colicinogenic strains and wild-type enterobacteria isolated from polluted river water. The effect of plasmid-carriage on the survival of enterobacteria was examined in river water and also in serum.

Item Type: Thesis (Doctor of Philosophy (PhD))
DOI/Identification number: 10.22024/UniKent/01.02.94429
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Subjects: Q Science > QH Natural history > QH301 Biology
Divisions: Divisions > Division of Natural Sciences > Biosciences
SWORD Depositor: SWORD Copy
Depositing User: SWORD Copy
Date Deposited: 14 Jul 2023 15:06 UTC
Last Modified: 14 Jul 2023 15:07 UTC
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