Biomaterial Database

A fluorometric beta-glucuronidase assay for analysis of bacterial growth in milk. 1995

W Fang, and M Vikerpuur, and M Sandholm

Department of Pharmacology and Toxicology, College of Veterinary Medicine, Helsinki, Finland.

The growth of common mastitis-causing bacteria in milk was followed by a fluorometric technique based on the release of fluorescent 4-methylumbelliferone (4-MU) from 4-methylumbelliferyl-beta-D-glucuronide by the beta-glucuronidase of bacterial or milk origin. Three of four Escherichia coli strains, all four strains of Streptococcus uberis (4/4) and Streptococcus agalactiae (4/4) produced beta-glucuronidase. Four Staphylococcus aureus strains (4/4) and one E. coli strain, though unable to produce the enzyme, activated the milk beta-glucuronidase most probably by lowering the pH of bacterial cultures in milk for optimum activity of the indigenous enzyme. The beta-glucuronidase of milk, Str. uberis and Str. agalactiae origin had similar optimum pH ranges (5.3-6.6) while E. coli beta-glucuronidase was more active at neutral or slightly alkaline pH (6.8-7.7). The increase of beta-glucuronidase activity in milk cultures of E. coli, Str. uberis, Str. agalactiae and S. aureus seemed to parallel the increase of colony forming units and were dependent on the inoculum size. The time to reach a predetermined enzyme threshold in E. coli-milk cultures showed excellent linear relationship with the inoculum size.

UI	MeSH Term	Description	Entries
D008414	Mastitis, Bovine	INFLAMMATION of the UDDER in cows.	Bovine Mastitides,Bovine Mastitis,Mastitides, Bovine
D008892	Milk	The off-white liquid secreted by the mammary glands of humans and other mammals. It contains proteins, sugar, lipids, vitamins, and minerals.	Cow Milk,Cow's Milk,Milk, Cow,Milk, Cow's
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D005260	Female		Females
D005470	Fluorometry	An analytical method for detecting and measuring FLUORESCENCE in compounds or targets such as cells, proteins, or nucleotides, or targets previously labeled with FLUORESCENCE AGENTS.	Fluorimetry,Fluorometric Analysis,Analysis, Fluorometric
D005966	Glucuronidase		Endo-beta-D-Glucuronidase,Endoglucuronidase,Exo-beta-D-Glucuronidase,beta-Glucuronidase,Endo beta D Glucuronidase,Exo beta D Glucuronidase,beta Glucuronidase
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013210	Staphylococcus	A genus of gram-positive, facultatively anaerobic, coccoid bacteria. Its organisms occur singly, in pairs, and in tetrads and characteristically divide in more than one plane to form irregular clusters. Natural populations of Staphylococcus are found on the skin and mucous membranes of warm-blooded animals. Some species are opportunistic pathogens of humans and animals.
D013291	Streptococcus	A genus of gram-positive, coccoid bacteria whose organisms occur in pairs or chains. No endospores are produced. Many species exist as commensals or parasites on man or animals with some being highly pathogenic. A few species are saprophytes and occur in the natural environment.