Methods and compositions for detecting bacterial contamination

A method of detecting bacterial contamination of a platelet sample by any of at least five bacterial genera, comprising:

• (a) subjecting the sample or a portion thereof to a nucleic acid amplification reaction under conditions to yield a detectable amount of an amplicon of no more than about 800 bases in a single reaction mixture, said reaction mixture comprising a single primer pair having a first primer and a second primer and a single detectable probe, wherein the first primer and the second primer each hybridizes to a separate conserved region of 16S rRNA polynucleotide, and the primer pair flanks the amplicon, wherein the amplicon comprises a conserved sequence to which the detectable probe hybridizes, and the conserved region is identical among the at least five bacterial genera,
• wherein the conserved region is selected from the group consisting of from 9 to 28, from 32 to 48, from 888 to 903, from 908 to 937, from 975 to 994, from 957 to 981, from 1093 to 1125, from 1184 to 1206, from 1231 to 1252, from 1378 to 1396, from 1398 to 1422, or from 1496 to 1516, of 16S rRNA of Staphylococcus aureus (GenBank accession Number NC_007622) or the corresponding region in a genome of any one of the at least five bacterial genera;
• and
• (b) detecting hybridization to the amplicon by the probe, wherein the hybridization by the probe yields a detectable signal indicative of bacterial contamination of the platelet sample by any of the at least five bacterial genera.