ANALYSIS OF THE ANAPLASMA-MARGINALE GENOME BY PULSED-FIELD ELECTROPHORESIS

Citation
Ar. Alleman et al., ANALYSIS OF THE ANAPLASMA-MARGINALE GENOME BY PULSED-FIELD ELECTROPHORESIS, Journal of General Microbiology, 139, 1993, pp. 2439-2444
Citations number
24
Categorie Soggetti
Microbiology
ISSN journal
00221287
Volume
139
Year of publication
1993
Part
10
Pages
2439 - 2444
Database
ISI
SICI code
0022-1287(1993)139:<2439:AOTAGB>2.0.ZU;2-1
Abstract
Anaplasma marginale is a rickettsial parasite of bovine erythrocytes c ausing world-wide economic losses in livestock production. Despite its importance, little is known about this rickettsia at a molecular leve l because it has not been cultured in vitro, and there is no small-ani mal model. Although several genes have been cloned and sequenced, the gross genome structure of the organism has not yet been well character ized. We separated intact bovine erythrocytes from leucocytes, and det ermined the genome size of A. marginale by use of restriction endonucl ease cleavage and pulsed-field gel electrophoresis (PFGE). A value of 56 mol % G + C was obtained for this genome by spectral analysis. Undi gested A. marginale DNA failed to migrate under several different elec trophoretic conditions, indicating a circular genome. Digestions of in tact A. marginale DNA were performed using restriction endonucleases N otI, SfiI and PacI. Complete digestion with SfiI resulted in 12 distin ct bands ranging in size from 14 to 170 kbp. Total size determined by addition of SfiI-digested fragments was approximately 1200 kbp. PacI c leaved the A. marginale genome from three different isolates into just three fragments, of 598, 557 and 97 kbp. Incomplete digestion produce d a band measuring 1250 kbp. These results indicate that A. marginale has a circular genome between 1200 and 1260 kbp, with a G + C content of 56 mol %.