title: Membrane association of the deoxyribonucleic acid growing-point region in Mycoplasma gallisepticum.
abstract: Newly replicated deoxyribonucleic acid (DNA) in Mycoplasma gallisepticum A5969 is membrane associated. Cells pulse-labeled 1 to 3 min with (3)H-thymidine are lysed by a freeze-thaw procedure. After brief sonic treatment to shear the DNA, differential centrifugation gives a cell fraction (P2) that is enriched sevenfold for pulse-labeled DNA. P2 contains 80% of the total adenosine triphosphatase activity, 65% of the total cholesterol, and morphologically intact terminal bleb structures. Three to four minutes are needed to fully label the DNA growing-point region, whereas 7 to 8 min are required to "chase" 50% of the (3)H-labeled DNA. This pulse-chase removes 80 to 85% of the nascent DNA from the P2 fraction.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D001426:Bacterial Proteins / Q000032:analysis; D001431:Bacteriological Techniques; D001433:Bacteriolysis; D002247:Carbon Isotopes; D002458:Cell Fractionation; D002462:Cell Membrane / Q000032:analysis* / Q000201:enzymology; D002784:Cholesterol / Q000032:analysis; D004261:DNA Replication; D004269:DNA, Bacterial / Q000032:analysis*; D007553:Isotope Labeling; D008854:Microscopy, Electron; D009174:Mycoplasma / Q000032:analysis* / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D012329:RNA, Bacterial / Q000032:analysis; D013347:Subcellular Fractions / Q000032:analysis; D013936:Thymidine / Q000378:metabolism; D014316:Tritium; D014529:Uridine / Q000378:metabolism; D014732:Vibration
chemical_list: D001426:Bacterial Proteins; D002247:Carbon Isotopes; D004269:DNA, Bacterial; D012329:RNA, Bacterial; D014316:Tritium; D002784:Cholesterol; D000251:Adenosine Triphosphatases; D013936:Thymidine; D014529:Uridine