Comparison of transcription-mediated amplification and growth-based methods for the quantitation of Enterococcus bacteria in environmental waters.

An assay based on transcription-mediated amplification (TMA) technology was used to quantitate Enterococcus fecal indicator bacteria in environmental water samples. The results generated by this and two growth-based methods relative to the 104 most-probable-number or CFU-per-100-ml threshold show that the three methods are in good qualitative agreement when tested against a range of water samples taken from different locations. The results demonstrate sensitive and rapid detection (approximately 4 h from sample collection to result) and quantitation of Enterococcus bacteria compared to the results with the growth-based methods.

Identification of sequences required for the import of human protoporphyrinogen oxidase to mitochondria.

Protoporphyrinogen oxidase (PPOX; EC 1.3.3.

Functional studies of mutations in the human protoporphyrinogen oxidase gene in variegate porphyria.

The autosomal dominant disorder, variegate porphyria (VP), results from mutations in the protoporphyrinogen oxidase (PPOX) gene. We have investigated the effects of 22 disease-associated missense mutations in this gene on enzyme activity. Mutants were generated in the expression plasmid pHPPOX by site-directed mutagenesis.