ARS | Publication request: Expression and Subcellular Location of a Leucine Aminopeptidase of Mycoplasma Gallinarum

Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 15, 2003
Publication Date: March 5, 2004
Citation: Wan, X., Branton, S.L., Hughlett, M.B., Pharr, G.T. 2004. Expression and subcellular location of a leucine aminopeptidase of mycoplasma gallinarum. Poultry Science. 3(1):70-74.

Interpretive Summary: Mycoplasma gallinarum is one of the most frequently isolated mycoplasmas found in poultry. Because Mycoplasma gallinarum is found so commonly yet causes no disease, we are interested in using this organism to better understand other closely related mycoplasmas which do cause disease in poultry and cost the poultry industry in excess of $140 million dollars annually. This study was conducted to determine the specific location within the Mycoplasma gallinarum organism of a particular enzyme ' leucine aminopeptidase. This enzyme which is responsible for allowing the organism to digest the amino acid leucine was determined to be present in the cytoplasm of the organism. This determination will be important for evaluating its role in host adaptation of Mycoplasma gallinarum in poultry and therefore offer insight into how deleterious mycoplasmas cause disease in poultry.

Technical Abstract: Mycoplasma gallinarum exists as a commensal with a host range that includes most poultry and some mammals. This property of M. gallinarum may reflect unique mechanisms for colonization and persistence in various hosts. In previous studies a leucine aminopeptidase (LAP) gene candidate was cloned from a M. gallinarum recombinant genomic library and characterized. Here we evaluate the LAP gene from M. gallinarum at the protein level. A recombinant fusion protein was purified and employed as an antigen to immunize chickens to obtain polyclonal anti-LAP serum. The antiserum was utilized to identify the subcellular location by immuoblotting with Triton X-114 partitions of M. gallinarum proteins. The results of these experiments suggest that the LAP gene product is located in the cytoplasmic fraction of the M. gallinarum cell.