Bifani JP, Li LL, Kapur V, Kreiswirth BN; American Society for Microbiology. General Meeting.

Abstr Gen Meet Am Soc Microbiol. 1997 May 4-8; 97: 563 (abstract no. U115).

Public Health Research Institute, TB Center, New York, NY.

Mycobacterium species display high lipolytic activity. Over 30 different species of Mycobacterium tested were found to hydrolize tributyrin and olive oil emulsified in 7H10 agar plates. Hydrolysis was distinguished by the generation of a clear zone around the colonies. MTB was found to have at least 5 different lipases. Four of them have been cloned and expressed in E. coli and 3 of these (TBLip2; TBLip7 and TBLip8) have been extensively characterized both at the nucleotide and protein level. TBLip2 consists of a 1284 nucleotide ORF encoding a 427 amino acid (aa) protein. The TBLip2 gene includes the characteristic lipase consensus catalytic serine (-Gly-X(1)-Ser-X(2)-Gly-) where X(1) is aspartate and X(2) alanine. The (-Gly-Asp-Ser-Ala-Gly-) fragment is homologous to the conserved human and rat hormone-sensitive lipase also found in Moraxella TA144. The first 100 amino acids from the N-terminus have been found to have a high degree of homology with various other putative ORF from MTB and M. leprae. TBLip7 is 957 nucleotides long encoding 318 aa protein while TBLip8 is 963 encoding a 320 aa protein. Both of these enzymes contain the consensus catalytic serine in the unusual (-Gly-Asp-Ser-Ala-Gly-) arrangement also found in TBLip2. In addition TBLip7 has a second potential catalytic serine (-Gly-Trp-Ser-Leu-Gly-). The three lipases were found to be present and conserved as single copy genes in the Mycobacterium complex but not in 32 other Mycobacterium species. Substrate specificity was determined spectrophotometrically using p-nitrophenyl-esters.

Publication Types:

• Meeting Abstracts

Keywords:

• Amino Acids
• Animals
• Carboxylic Ester Hydrolases
• Chymotrypsin
• Endopeptidases
• Humans
• Hydrolysis
• Lipase
• Rats
• Serine
• Sterol Esterase
• Substrate Specificity
• Trypsin
• enzymology

Other ID:

• 98928861

UI: 102235514

From Meeting Abstracts