UGA is a nonsense or termination (opal) codon throughout prokaryotes and eukaryotes. However, mitochondria use not only UGG but also UGA as a tryptophan codon. Here, we show that UGA also codes for tryptophan in Mycoplasma capricolum, a wall-less bacterium having a genome only 20-25% the size of the Escherichia coli genome. This conclusion is based on the following evidence. First, the nucleoti...

Members of the mycoplasmas are known to have some the smallest free-living prokaryotes. They are characterized by their small genomes (0.58 – 2.20 Mb) and lack of a cell wall [1]. The availability of complete genome sequences of several mycoplasmas provides a great opportunity to understand the minimal genome biology of these small bacteria [2]. Considerable advances have been made towards unde...

The 5' region of the rRNA operon, rrnA, of M. capricolum was cloned. Sequence analysis revealed two tRNA genes, tRNA(leu) and tRNA(lys), upstream to the promoter of the rRNA operon. The in vivo transcription start sites of the rRNA operon and of the tRNA genes were mapped. The same promoters used by M. capricolum RNA polymerase are also recognized by E. coli RNA polymerase both in vivo and in v...

Background: Contagious Caprine Pleuropneumonia (CCPP) is a devastating disease of goats caused by Mycoplasma capricolum subsp. Capripneumoniae (Mccp). The disease was first confirmed in Uganda in 1995 in Karamoja region. Contagious Caprine Pleuropneumonia negatively impacts on goats’ productivity but its extent and magnitude among the local communities in Uganda remain unknown. A cross sectiona...

The polyene antibiotic, filipin, binds to 3 beta-hydroxysterols. The initial rate of filipin-sterol association, monitored in a stopped-flow spectrophotometer, was first order in each reacting partner. The ratio of rate constants in intact mycoplasma cells relative to isolated, unsealed membranes provides an estimate of sterol distribution in the membrane bilayer. Cholesterol is distributed sym...

The synthesis of stable RNA in Mycoplasma capricolum was studied by [32P] labeling of cellular RNA of cells grown in a partially-defined medium in the presence or absence of an amino acid mixture supplement. The results indicate that M. capricolum employs the same stringent control mechanism used by E. coli cells, as judged by a decreased synthesis of stable RNA and accumulation of 5'-triphosph...

Two stable RNA species and their genes have been isolated from Mycoplasma capricolum, and the nucleotide sequences have been determined by partial RNA sequencing and sequencing of the genes. The RNAs are 92 and 105 nucleotides in length, respectively. The two RNAs reveal no sequence similarity to any stable RNA so far reported, indicating that these are novel RNA species. The RNAs, designated M...