Repair of thermal damage to the Escherichia coli nucleoid.

AUTOR(ES)

Pellon, J R

RESUMO

The folded chromosome or nucleoid of Escherichia coli was analyzed by low-speed sedimentation in neutral sucrose gradients after heat treatment (30 min at 50 degrees C) and subsequent incubation of cells at 37 degrees C for various times. Heat treatment resulted in in vivo association of the nucleoids with cellular protein and in an increase in sedimentation coefficient. During incubation at 37 degrees C, a fraction of the nucleoids, from heated cells, because dissociated from cellular protein and regained their characteristic sedimentation coefficients. The percentage of nucleoids which returned to their control sedimentation position in the sucrose gradients corresponded to the percentage of cells able to repair thermal damage as assayed by enumeration on agar plates.

Documentos Relacionados

• Biochemical characterization of nonintegrated plasmid-folded chromosome complexes: sex factor F and the Escherichia coli nucleoid.
• Autoradiographic analysis of diaminopimelic acid incorporation in filamentous cells of Escherichia coli: repression of peptidoglycan synthesis around the nucleoid.
• Identification and preliminary characterization of a mutant defective in the bacteriophage T4-induced unfolding of the Escherichia coli nucleoid.
• Repair response of Escherichia coli to hydrogen peroxide DNA damage.
• Repair of Radiation-Induced Damage to the Cell Division Mechanism of Escherichia coli1