The growth and long term survival of Acholeplasma laidlawii in media products used in biopharmaceutical manufacturing.

Acholeplasma laidlawii is a potential contaminant of bovine serum and has also been found as a contaminant in serum free cell culture media products. Anecdotal evidence of A. laidlawii contamination of tryptone soya broth circulated for a number of years before it was acknowledged that the organism could contaminate microbiological broth powders. The occasional occurrence of A. laidlawii in broth powders and possibly in powdered components of cell culture media as part of the normal bioburden poses a serious threat to routine pharmaceutical and biopharmaceutical operations where filtration is the sterilisation method of choice. Absence of visual evidence of contamination cannot be relied upon as there is variation with both organism strain and media product in the ability to produce turbidity. Strains of A. laidlawii which have been isolated from broth powders are not significantly different in temperature or media preferences from other strains. A. laidlawii is capable of growing to high titre at refrigeration and ambient temperatures in unsupplemented bacteriological sterility media or serum free cell culture media and can survive for prolonged periods in these products.