Nucleic Acid Precursor Requirements of Mycoplasma laidlawii

Abstract

The nucleic acid precursor requirements of Mycoplasma laidlawii strain A were determined by using a partially defined medium. Adenine, guanosine and cytidine were found to be the minimal growth requirements. However, best growth was obtained with undegraded RNA or oligoribo-nucleotides. Thymidine was not essential for growth when folinic acid was present in the medium; folic acid was completely inactive. M. laidawii utilized the 2[image]- and 3[image]-ribonucleotides most poorly. The dephosphorylation of these mononucleotides to nucleosides rendered them growth promoting.