Scientific Publications by FDA Staff

J Appl Microbiol 2011 Oct;111(4):904-14

Preparation of reference strains for validation and comparison of mycoplasma testing methods.

Dabrazhynetskaya A, Volokhov DV, Ikonomi P, Brewer A, Chang A, Chizhikov V

Aims: To optimize growth conditions for preparation of stocks of mycoplasma reference strains to obtain highly viable and disperse samples with low ratios of genomic copy (GC) number to that of colony forming units (CFU). These stocks are required for assessment of relative Limits of Detection (LOD) of alternative nucleic acid testing (NAT)-based methods in comparison to the conventional microbiological methods. Methods and Results: A kinetics study was used to assess the changes in ratios between the numbers of GC and CFU at different growth phases of six different mycoplasma cultures Acholeplasma laidlawii, Mycoplasma gallisepticum, Mycoplasma arginini, Mycoplasma fermentans, Mycoplasma orale and Mycoplasma pneumoniae. All tested mycoplasmas demonstrated low GC/CFU ratios (