https://mmbr.asm.org/content/mmbr/48/1/60.full.pdf

Mutagenesis and inducible responses to deoxyribonucleic acid damage in Escherichia coli.

Oxidative Nucleobase Modifications Leading to Strand Scission

INTRODUCTION .............................................................. 869 Enzymatic Repair of UV Damage in E. coli ......... .......................... 869 Error-Proof and Error-Prone Pathways of DNA Repair ....... ................. 871 The \"SOS\" Hypothesis: the Regulatory Role of DNA Damage ...... ............ 874 EVIDENCE FOR THE INDUCIBILITY OF ERROR-PRONE REPAIR (\"SOS REPAIR\") ACTIVITY ..................................................... 875 SOS Repair of Bacteriophage DNA ............ ............................... 875 SOS Repair of Bacterial DNA ................ ................................ 876 Evidence from studies of repair-deficient mutants ....... .................... 876 Evidence from studies of postreplication repair ........ ...................... 879 MANIFESTATIONS OF SOS REPAIR AND THEIR SIGNIFICANCE ..... ...... 879 Mutation Frequency Response to Increasing Fluence of UV Radiation ..... ..... 879 The UV Lesion Responsible for Induction of SOS Functions.................... 880 Kinetics of Induction and Decay of SOS Repair Activity ....... ................ 882 Time of Action of SOS Repair in UV Mutagenesis ...... ........................ 882 Cryptic Premutational Lesions Susceptible to SOS Repair ...................... 884 Mutator Effect of SOS Repair on Undamaged DNA ....... ..................... 885 PLASMIDS AND SOS REPAIR ................................................ 886 MECHANISM OF SOS REPAIR ............................................... 886 Mechanism of SOS Repair in Bacteriophage ......... .......................... 886 Mechanism of SOS Repair in Bacteria ........... ............................. 887 IMPLICATIONS OF SOS REPAIR FOR CARCINOGENESIS ................... 888 REGULATION OF SOS REPAIR AND OTHER UV-INDUCIBLE FUNCTIONS . 889 PROTEASES AND THE EXPRESSION OF SOS FUNCTIONS .................. 894 CONCLUSIONS ............................................................... 895 APPENDIX................................................................... 896 LITERATURE CITED ......................................................... 898

Ultraviolet mutagenesis and inducible DNA repair in Escherichia coli.

A hypothesis was proposed several years ago that Escherichia coli possesses an inducible DNA repair system (“SOS repair”) which is also responsible for induced mutagenesis. Some characteristics of the SOS repair are (1) it is induced or activated following damage to DNA, (2) it requires de novo protein synthesis, (3) it requires several genetic functions of which the best-studied are recA + and lex + of E. coli, and (4) the physiological and genetic requirements for the expression of SOS repair are suspiciously similar to those necessary for the prophage induction. The SOS repair hypothesis has already served as the working hypothesis for many experiments, some of which are briefly reviewed. Also, some speculations are presented to stimulate further discussions and experimental tests.

SOS repair hypothesis: phenomenology of an inducible DNA repair which is accompanied by mutagenesis.

Publisher Summary Escherichia coli is a universal host organism both for molecular cloning of DNA and for a diverse set of assays involving clones genes. This chapter discusses the major techniques and parameters that affect transformation of bacteria, focusing on E.coli . There are two major parameters involved in efficiently transforming a bacterial organism. The first is the method used to induce competence for transformation. There are two primary technical variations in this method: chemical induction of competence and high-voltage electroshock treatment (electroporation). Both the characteristic of the cells being transformed and the purpose of the transformation affect the choice of method. The second major parameter is the genetic constitution of the host strain of the organism being transformed; a variety of genes can dramatically influence the outcome of transformation experiments.

Plasmid transformation of Escherichia coli and other bacteria

https://www.cell.com/cell/pdf/0092-8674(83)90065-X.pdf

A temperature-sensitive mutant of E. coli exhibiting slow processing of exported proteins

The bacterial recA gene participates in the induction by UV irradiation of the clear mutation of phage λ and the Lac- mutation of bacteria. The necessary function is induced by irradiation of Rec+ bacteria and acts upon DNA irradiated with UV light.

Studies on radiation-sensitive mutants of E. coli

Koreaki Ito, * Michael Wittekind: Masayasu Nomura,+ Kiyotaka Shiba,* Takashi Yura,’ Akiko Miura* and Hiroko Nashimoto’ * Institute for Virus Research Kyoto University Kyoto 606, Japan + Institute for Enzyme Research University of Wisconsin Madison, Wisconsin 53706 *Institute of Medical Science University of Tokyo Tokyo 108, Japan Summary A temperature-sensitive E. coli mutant with a mu- tation in the spc ribosomal protein operon was found to have a conditional defect in the processing of precursor proteins destined for the periplasmic space or the outer membrane. At high tempera- tures, significant amounts of precursor proteins having unprocessed signal sequences are detected in the mutant cell by pulse-labeling. The precursors are processed at very slow rates during a subse- quent chase. Genetic analysis indicates that the mutation impairs the function of a gene, termed secY, located at the promoter-distal part of the spc operon. The secY gene is distinct from those genes previously known to specify ribosomal proteins, yet it is within the spc operon. It is suggested that the product of the secY gene is a component of the cellular apparatus that is essential for protein se- cretion across the cytoplasmic membrane. The gene secY is probably identical with prlA,previously identified as a suppressor of signal sequence mu- tations. Introduction A number of proteins are found outside the cytoplas- mic membrane in E. coli. Passage of these proteins across the membrane occurs either cotranslationally (Smith et al., 1977) or posttranslationally (Wickner, 1980). According to the cotranslational model of pro- tein translocation across the membrane (Blobel and Dobberstein, 1975), the signal peptide in the nascent precursor molecule initiates the translocation process by facilitating its binding to the membrane. This is followed by specific interaction between the ribo- somes and the membrane to form membrane-bound polysomes. Transfer of the polypeptide through the membrane occurs concomitantly with translation of the remaining part of the protein. In this series of events, ribosomes could have an active role in the translocation process. One approach to studying the role (if any) of the ribosomes in protein localization processes is to isolate mutants that have altered ri- bosomes and exhibit abnormal localization of the ex- ported proteins. In the bacterial system, Emr et al. (1981) have identified mutations in E. coli within one of the ribo- somal protein (r-protein) operons at 72 min. These mutations, termed

Akiko Miura

Papers

A temperature-sensitive mutant of E. coli exhibiting slow processing of exported proteins

Studies on radiation-sensitive mutants of E. coli

Mutant of E. coli Exhibiting Slow Processing of Exported Proteins

The mutagenic action of sodium bisulfite.

Structure of nucleohistone. III. Interaction with toluidine blue