Abstract: Methods for detecting microorganisms, in particular detection of bacteria and methods for measuring enzyme activity, such as Deoxyribonucleic acid (DNA) polymerase activity are disclosed. The aforesaid methods include, but are not limited to such methods performed on microbial crude lysates, useful for determining microbial enzyme activities, which can be linked to amplification signal generators such as real-time Polymerase Chain Reaction (PCR) techniques, thereby enabling determination of microbial pathogens in samples such as unpurified blood and other body fluids. Moreover, the disclosed embodiments also relate to reagents for use in such methods, and to test kits comprising such reagents for carrying out the methods.

Abstract: An assay kit of reagents including a nucleic acid capable of acting as substrate for polymerase microorganism activity useful in a method of detecting polymerase activity as an indicator of the presence of a micro-organism in a sample are disclosed. The disclosed embodiments also relate to reagents for use in such methods, and to test kits comprising such reagents for carrying out the methods.

Abstract: A method of detecting a ligase expressing micro-organism in a sample comprises steps of treating the sample under conditions that inhibit the activity of ATP-dependent ligase from mammalian cells but which do not inhibit the activity of the microbial ligases, contacting the sample or a portion of the sample with a nucleic acid molecule which acts as a substrate for ligase activity in the sample, incubating the thus contacted sample under conditions suitable for ligase activity; and specifically determining the presence and/or the amount of a ligated nucleic acid molecule resulting from the action of the ligase on the substrate nucleic acid molecule to indicate the presence of the ligase expressing micro-organism. The micro-organism may be a fungus or a bacterium or both. High pH conditions may be employed to inactivate mammalian ligases. Related kits are described.

Abstract: A method of detecting a ligase expressing micro-organism in a sample comprises steps of treating the sample under conditions that inhibit the activity of ATP-dependent ligase from mammalian cells but which do not inhibit the activity of the microbial ligases, contacting the sample or a portion of the sample with a nucleic acid molecule which acts as a substrate for ligase activity in the sample, incubating the thus contacted sample under conditions suitable for ligase activity; and specifically determining the presence and/or the amount of a ligated nucleic acid molecule resulting from the action of the ligase on the substrate nucleic acid molecule to indicate the presence of the ligase expressing micro-organism. The micro-organism may be a fungus or a bacterium or both. High pH conditions may be employed to inactivate mammalian ligases. Related kits are described.