Introduction
James F. Kane in Multifunctional Proteins: Catalytic/Structural and Regulatory, 2019
Another interesting multifunctional protein is the so-called “Protein X” or the recA gene product of E. coli. This protein has the following properties: protease activity18–20 catalyzes the formation of D loops, that is, binding of a single stranded DNA molecule to its homologous counterpart in a double stranded DNA molecule,21,22 binding and hydrolysis of ATP,18,22 and association with membrane.23,24 Although the molecular basis for the many functions of the recA protein are largely unknown, the regulatory function of the recA protein appears to be related to its protease activity. That is, the recA gene product controls its own synthesis by proteolytically degrading the repressor protein synthesized by the lexA gene. This mechanism of autogenous control is unique among those proposed in this volume where control appears to be at the level of gene transcription or translation.
Mutagenic Consequences Of Chemical Reaction with DNA
Philip L. Grover in Chemical Carcinogens and DNA, 2019
A second problem is that it is unlikely that the recA+ gene product is solely a protease. For one thing, far too much is formed, up to 4% of the total cell protein.93 Gudas and Pardee93 also showed that protein X bound specifically to single-stranded DNA, and it is possibly this property which enhances the survival of uvr+ recA tsl mutants.78,97 These mutants appear to produce constitutively an otherwise inactive recA gene product.93 Further difficulties arise in reconciling the apparent constitutive nature of recombination, with the apparent inducible nature of other rec-lex functions, and it is these considerations that have led Morand et al. to formulate their model.92
Role of telomeres and telomerase in aging and cancer
J. K. Cowell in Molecular Genetics of Cancer, 2003
The gene responsible for WS (WRN) has been cloned and encodes a protein with homology to the E. coli RecQ (Yu et al., 1996). The RecQ protein binds single-stranded DNA and has a 3’→5’ helicase activity (Umezu et al., 1990). That helicase function is dependent on ATP hydrolysis and is stimulated (> 100 fold) by single strand binding protein (Umezu and Nakayama, 1993). RecQ can resolve a wide variety of substrates including recombinational joint molecules generated by RecA protein (Harmon and Kowalczykowski, 1998). These properties of RecQ led to the suggestion that it may improve the fidelity of recombination by dissociating illegitimate recombination events that are initiated through microhomology. Reintroduction of the WRN gene into WS cells complements the premature senescence phenotype of WS cells (Hisama et al., 2000). Similarly, introduction of an exogenous hTERT gene into WS cells yields suppression of senescence of WS cells, as it does for most other cell types tested (Ouellette et al., 2000; Wyllie et al., 2000). Another report indicates that the introduction of hTERT gene into WS cells can render partial correction of the 4NQO sensitivity of those cells (Hisama et al., 2000). This suggests that the 4NQO sensitivity is intimately linked to telomere length.
Gut Bacteroides species in health and disease
Published in Gut Microbes, 2021
The Bfr genes katA, ahpC and tpx encode catalase, alkyl hydroperoxidase and thioredoxin peroxidase, respectively. These proteins assist in the oxidative stress response by detoxifying peroxides.115 Bacterioferritin co-migratory proteins are encoded within the genomes of numerous bacterial species. These proteins are members of the thiol-specific antioxidant protein family and play key roles in the prevention of free radical formation and resultant cellular oxidative damage.116 Studies with Bfr by Nicholson et al. suggested that the bacterioferritin co- migratory protein, encoded within the recA operon, may play a role in maintaining metabolic fitness and genomic integrity in response to oxidative stress.117 This may be accomplished by assisting in the reduction of hydroperoxides, thereby preventing lipid oxidation and DNA damage during oxidative stress.
Cost of fear and radiation protection actions: Washington County, Utah and Fukushima, Japan {Comparing case histories}
Published in International Journal of Radiation Biology, 2020
Bruce W. Church, Antone L. Brooks
NOTE: Downwinder Areas: The Act covers physical presence in certain counties located downwind from the Nevada Test Site. In the State of Utah, the counties include Beaver, Garfield, Iron, Kane, Millard, Piute, San Juan, Sevier, Washington, and Wayne; in the State of Nevada, the counties include Eureka, Lander, Lincoln, Nye, White Pine, and that portion of Clark County that consists of townships 13 through 16 at ranges 63 through 71; and in the State of Arizona, the counties include Apache, Coconino, Gila, Navajo, Yavapai, and that part of Arizona that is north of the Grand Canyon. A claimant must establish physical presence in the Downwinder area for two years during the period beginning on January 21, 1951, and ending on October 31, 1958, or for the entire period beginning on June 30, 1962, and ending on July 31, 1962, and a subsequent diagnosis of a specified compensable disease. All claims under RECA must be filed by July 9, 2022. In accordance with Section 8(a) of RECA, any claim received after July 9, 2022, will be barred.
In vitro and in vivo efficacy of Caenorhabditis elegans recombinant antimicrobial protein against Gram-negative bacteria
Published in Biofouling, 2019
Dilawar Ahmad Mir, Krishnaswamy Balamurugan
The proteomic data analysis revealed that the ABF-1 protein affected cell cycle associated proteins (Tables 2 and 3) (RuvB helicase, RecA, mukF, endonuclease-VIII, Rho, rpoC, yajQ, cspA, greA, t1627, dnaB and rcsB). Among these, RuvB is a helicase protein that mediates DNA Holliday junction migration by localizing the denaturation and reannealing and RecA proteins play a role in homologous recombination, promoting synapsis, heteroduplex formation, and strand exchange between homologous DNAs (Iype et al. 1994). The mukF protein is involved in chromosome condensation, which is key step for cell division (Yamazoe et al. 1999). The endonuclease-VIII (NEI) protein acts as a DNA glycosylase that recognizes and removes DNA bases damaged by oxidation or mutagenic agents (Jiang et al. 1997). Collectively, these proteins play an important role in DNA damage, DNA recombination, DNA repair, SOS response and damaged DNA binding (Igarashi and Ishihama 1991; Borukhov et al. 1992; Bae et al. 2000; Skunca et al. 2013).
Related Knowledge Centers
- Archaea
- Autocatalysis
- Bacteria
- DNA
- DNA Repair
- Eukaryote
- Protease
- Protein
- DNA
- Rad51
- DNA Repair
- Sos Response