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Tackling problem microbes 
When microbiological problems strike, rapid and reliable solutions are essential. Using the latest molecular techniques we extended our portfolio of methods for fast and definitive identification of both pathogens and spoilage organisms. For example, the identity of a presumptive Salmonella can be reliably confirmed in four hours using DNA amplification (PCR). We also use microbial DNA sequencing - now considered to be the gold standard for microbial identification. We have a Microseq® system from Applied Biosystems which combines the latest in sequencing technology with improved analysis software and a validated database of over 1700 bacterial species, as well as selected yeasts. The system can be used for microbes isolated from food, drink, and environmental or other samples. Even 'unknown' organisms can be identified by sequencing their genes and comparing these with international gene sequence databases. As well as definitively identifying pathogens, this approach has helped to solve bacterial spoilage problems in food ingredients, dairy products and flavoured drinks. Once the problem organism has been identified, it is possible to assess whether it poses a safety risk or is likely to survive a process such as a heat treatment, and take appropriate measures. Tracing the source of contamination by strain typing can also enable effective intervention. Ribotyping and 'rep PCR' are now widely accepted as highly effective ways of 'fingerprinting' food and environmental isolates of pathogens such as Listeria monocytogenes.Where strains match, the source of contamination can be targeted with hygiene and other preventative measures. Contact: Dr Suzanne Jordan |