Acid phosphatase test proves superior to standard phenotypic identification procedure for Clostridium perfringens strains isolated from water

• Published in: Journal of microbiological methods 2011-11, Vol.87 (2), p.189-194
• Main Authors: Ryzinska-Paier, G., Sommer, R., Haider, J.M., Knetsch, S., Frick, C., Kirschner, A.K.T., Farnleitner, A.H.
• Format: Article
• Language: English
• Subjects: acid phosphatase; Acid Phosphatase - analysis; Acid Phosphatase - metabolism; Acid phosphatase test; Bacterial Proteins - analysis; Bacterial Proteins - metabolism; Biological and medical sciences; Clostridium perfringens; Clostridium perfringens - enzymology; Clostridium perfringens - genetics; Clostridium perfringens - isolation & purification; Enzyme Assays - methods; Faecal pollution; feces; Feces - microbiology; fermentation; Fundamental and applied biological sciences. Psychology; Gas Gangrene - diagnosis; Gas Gangrene - microbiology; gelatin; Genotypic confirmation; Humans; labor; lactose; Microbiology; nitrate reduction; Phenotypic confirmation; pollution; polymerase chain reaction; Polymerase Chain Reaction - methods; Water; Water Microbiology; water treatment
• ISSN: 0167-7012; 1872-8359
• DOI: 10.1016/j.mimet.2011.08.006

Clostridium perfringens is used as an indicator for persistent faecal pollution as well as to monitor the efficacy of water treatment processes. For these purposes, differentiation between C. perfringens and other Clostridia is essential and is routinely carried out by phenotypic standard tests as proposed in the ISO/CD 6461-2:2002 (ISO_LGMN: lactose fermentation, gelatine liquidation, motility and nitrate reduction). Because the ISO_LGMN procedure is time consuming and labour intensive, the acid phosphatase test was investigated as a possible and much more rapid alternative method for confirmation. The aim of our study was to evaluate and compare confirmation results obtained by these two phenotypic methods using genotypically identified strains, what to our knowledge has not been accomplished before. For this purpose, a species specific PCR method was selected based on the results received for type strains and genotypically characterised environmental strains. For the comparative investigation type strains as well as presumptive C. perfringens isolates from water and faeces samples were used. The acid phosphatase test revealed higher percentage (92%) of correctly identified environmental strains (n=127) than the ISO_LGMN procedure (83%) and proved to be a sensitive and reliable confirmation method. ► The identification of Clostridium perfringens by routine phenotypic standard tests is very time consuming. ► We investigated acid phosphatase test as a possible and much more rapid alternative method. ► Evaluation was performed on type strains and genotypically identified isolates of water and faeces. ► The new confirmation method proved to be sensitive, reliable and feasible. ► It will help to enhance the quality of C. perfringens identification in water quality monitoring.