Amanda Jones

Detection of carboxypeptidases as taxonomic markers for Gram-negative bacteria

The use of seven benzoyl‐ L‐amino acids for the detection of carboxypeptidase activities in strains of Gram‐negative aerobic and facultatively anaerobic bacteria is reported. A simple overnight assay was designed using ninhydrin for the demonstration of the amino acid released by hydrolysis. Detection of carboxypeptidase activity was shown to have some taxonomic relevance within the Enterobacteriaceae; it was also useful for differentiation within the genus Acinetobacter and for distinction between Pseudomonas aeruginosa and Pseudomonas fluorescens.

Mechanical prophylaxis: Bacterial colonisation and sterilisation

Mechanical forms of deep venous thrombosis (DVT) prophylaxis have been shown to be effective. One factor that has reduced their widespread acceptance is the relatively high cost. Multi-use would greatly reduce the cost but could increase risks of cross-infection. We have investigated the bacterial load on boots after a single use and identified many species of bacteria including multi-resistant strains and others implicated in hospital- acquired infection. These could represent a considerable risk during multi-use. In the second part of the study we have investigated ways of sterilising the boots and have found ethylene oxide to be a low cost and completely effective method of sterilisation.