Method and kit for detection of microorganism

A kit for detecting live cells of a microorganism in a test sample by distinguishing the live cells from dead cells or injured cells by a nucleic acid amplification method, which comprises the following components:

• 1) an agent capable of covalently binding to DNA or RNA of the microorganism by irradiation with light having a wavelength of 350 nm to 700 nm;
• 2) an agent for suppressing a nucleic acid amplification inhibitory substance, magnesium salt, and either one of an organic acid salt and a phosphoric acid salt;
• and
• 3) a primer or primers for amplifying a target region of the DNA or RNA of the microorganism to be detected by a nucleic acid amplification method,
• wherein the agent for suppressing a nucleic acid amplification inhibitory substance is one or more selected from the group consisting of albumin, dextran, T4 gene 32 protein, acetamide, betaine, dimethyl sulfoxide, formamide, glycerol, polyethylene glycol, soybean trypsin inhibitor, α2-macroglobulin, tetramethylammonium chloride, lysozyme, phosphorylase and lactate dehydrogenase.