Nucleic acid assay system for tier II laboratories and moderately complex clinics to detect HIV in low-resource settings.

There is a clear need for an instrument-free molecular diagnostic system for detecting human immunodeficiency virus type 1 (HIV-1) RNA or DNA that can be used in developing countries. Such a test could be used for early diagnosis of HIV-1 infection during infancy and could serve as a surrogate end point for vaccine trials. We developed the IsoAmp HIV-1 assay (BioHelix Corporation), which targets the HIV-1 gag gene with use of isothermal reverse-transcription helicase-dependent amplification chemistry.

Comparative structural, kinetic and inhibitor studies of Trypanosoma brucei trypanothione reductase with T. cruzi.

As part of a drug discovery programme to discover new treatments for human African trypanosomiasis, recombinant trypanothione reductase from Trypanosoma brucei has been expressed, purified and characterized. The crystal structure was solved by molecular replacement to a resolution of 2.3A and found to be nearly identical to the T.

Application of isothermal helicase-dependent amplification with a disposable detection device in a simple sensitive stool test for toxigenic Clostridium difficile.

Enzyme immunoassays (EIAs) are commonly used for the diagnosis of cases of Clostridium difficile-associated diarrhea (CDAD). However, these EIAs have high false-negative rates, even in patients with severe clinical disease. We have developed an IsoAmp CDAD test using a simple and user-friendly procedure to identify toxigenic C.

Primase-based whole genome amplification.

In vitro DNA amplification methods, such as polymerase chain reaction (PCR), rely on synthetic oligonucleotide primers for initiation of the reaction. In vivo, primers are synthesized on-template by DNA primase. The bacteriophage T7 gene 4 protein (gp4) has both primase and helicase activities.