Practice question

Mycoplasma contamination in mammalian cell cultures is difficult to detect by microscopy or culture because organisms lack a cell wall and grow slowly. PCR targeting conserved 16S rRNA or 16S-23S spacer regions offers highly sensitive, specific, and rapid detection of few genome copies in culture supernatant. Southern hybridization requires larger DNA amounts and is less sensitive. ELISA and Western hybridization detect proteins and lack broad Mycoplasma genus coverage. Hence PCR is the gold standard for routine screening mandated by cell banks, preventing altered growth, metabolism, and experimental artifacts.