Biomaterial Database

Experimental and theoretical cross sections for Escherichia coli mutants B, B/r, and Bs-1 after heavy-ion irradiation. 1993

R Katz, and R Zachariah

Department of Physics and Astronomy, University of Nebraska, Lincoln 68588-0111.

Data for the inactivation of three Escherichia coli mutants by energetic heavy ions are fitted by the track theory of a one-hit detector in an extended target mode. The respective E0's are 46, 36.5, and 12.6 Gy for E. coli B, B/r, and Bs-1 and a0, the assumed target radius, is 0.5 microns for all three. The parameter E0, the D37 with gamma rays, is measured directly, while a0 is fitted to the data. It is significant that neither a point target model nor calculations with a0 = 0.2 and 1.0 micron fit the data. Our fitted target radius, a0, approximates the size of the bacterium. These results raise questions as to why the E. coli mutants are one-hit detectors, and concerning the differences in the E0's in relation to a mechanistic interpretation of cell killing.

UI	MeSH Term	Description	Entries
D007477	Ions	An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009686	Nuclear Physics	The study of the characteristics, behavior, and internal structures of the atomic nucleus and its interactions with other nuclei. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Nuclear Physic,Physic, Nuclear,Physics, Nuclear
D011831	Radiation Genetics	A subdiscipline of genetics that studies RADIATION EFFECTS on the components and processes of biological inheritance.	Genetics, Radiation
D011836	Radiation Tolerance	The ability of some cells or tissues to survive lethal doses of IONIZING RADIATION. Tolerance depends on the species, cell type, and physical and chemical variables, including RADIATION-PROTECTIVE AGENTS and RADIATION-SENSITIZING AGENTS.	Radiation Sensitivity,Radiosensitivity,Sensitivity, Radiation,Tolerance, Radiation,Radiation Sensitivities,Radiation Tolerances,Radiosensitivities,Sensitivities, Radiation,Tolerances, Radiation
D004735	Energy Transfer	The transfer of energy of a given form among different scales of motion. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed). It includes the transfer of kinetic energy and the transfer of chemical energy. The transfer of chemical energy from one molecule to another depends on proximity of molecules so it is often used as in techniques to measure distance such as the use of FORSTER RESONANCE ENERGY TRANSFER.	Transfer, Energy
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D000054	Acceleration	An increase in the rate of speed.	Accelerations