Biomaterial Database

Rescue of Escherichia coli cells from UV-induced death and filamentation by caspase-3 inhibitor. 2019

Surbhi Wadhawan, and Satyendra Gautam

Food Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, 400085, India.

Escherichia coli cells have been observed earlier to display caspase-3-like protease activity (CLP) and undergo programmed cell death (PCD) when exposed to gamma rays. The presence of an irreversible caspase-3 inhibitor (Ac-DEVD-CMK) during irradiation was observed to increase cell survival. Since radiation is known to induce SOS response, the effect of a caspase-3 inhibitor on SOS response was studied in E. coli. UV, a well-known SOS inducer, was used in the current study. Cell filamentation in E. coli upon UV exposure was found to be inhibited by ninefold in the presence of a caspase-3 inhibitor. CLP activity was found to increase twofold in UV-exposed cells than in control (non-treated) cells. Further, bright fluorescing filaments were observed in UV-exposed E. coli cells treated with FITC-DEVD-FMK, a fluorescent dye tagged with an irreversible caspase-3 inhibitor (DEVD-FMK), indicating the presence of active CLP in these cells. Unlike caspase-3 inhibitor, a serine protease inhibitor, phenylmethanesulfonyl fluoride (PMSF), was not found to improve cell survival after UV treatment. Additionally, a SOS reporter system known as SIVET (selectable in vivo expression technology) assay was performed to reconfirm the inhibition of SOS induction in the presence of caspase-3 inhibitor. SIVET assay is used to quantify cells in which the SOS response has been induced leading to a scorable permanent selectable change in the cell. The SIVET induction frequency (calculated as the ratio of SIVET-induced cells to total viable cells) increased around tenfold in UV-exposed cultures. The induction frequency was found to decrease significantly to 51 from 80% in the cells pre-incubated with caspase-3 inhibitor. On the contrary, caspase-3 inhibitor failed to improve cell survival of E. coli ΔrecA and E. coli DM49 (SOS non-inducible) cells post UV treatment. Summing together, the results indicated a possible linkage of SOS response and the PCD process in E. coli. The findings also indicated that functional SOS pathway is required for CLP-like activity; however, the exact mechanism remains to be elucidated.

UI	MeSH Term	Description	Entries
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
D013014	SOS Response, Genetics	An error-prone mechanism or set of functions for repairing damaged microbial DNA. SOS functions (a concept reputedly derived from the SOS of the international distress signal) are involved in DNA repair and mutagenesis, in cell division inhibition, in recovery of normal physiological conditions after DNA repair, and possibly in cell death when DNA damage is extensive.	SOS Response (Genetics),SOS Box,SOS Function,SOS Induction,SOS Region,SOS Repair,SOS Response,SOS System,Box, SOS,Function, SOS,Functions, SOS,Genetics SOS Response,Genetics SOS Responses,Induction, SOS,Inductions, SOS,Region, SOS,Regions, SOS,Repair, SOS,Repairs, SOS,Response, Genetics SOS,Response, SOS,Response, SOS (Genetics),Responses, Genetics SOS,Responses, SOS,Responses, SOS (Genetics),SOS Functions,SOS Inductions,SOS Regions,SOS Repairs,SOS Responses,SOS Responses (Genetics),SOS Responses, Genetics,SOS Systems,System, SOS,Systems, SOS
D014466	Ultraviolet Rays	That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.	Actinic Rays,Black Light, Ultraviolet,UV Light,UV Radiation,Ultra-Violet Rays,Ultraviolet Light,Ultraviolet Radiation,Actinic Ray,Light, UV,Light, Ultraviolet,Radiation, UV,Radiation, Ultraviolet,Ray, Actinic,Ray, Ultra-Violet,Ray, Ultraviolet,Ultra Violet Rays,Ultra-Violet Ray,Ultraviolet Black Light,Ultraviolet Black Lights,Ultraviolet Radiations,Ultraviolet Ray
D015842	Serine Proteinase Inhibitors	Exogenous or endogenous compounds which inhibit SERINE ENDOPEPTIDASES.	Serine Endopeptidase Inhibitor,Serine Endopeptidase Inhibitors,Serine Protease Inhibitor,Serine Protease Inhibitors,Serine Proteinase Antagonist,Serine Proteinase Antagonists,Serine Proteinase Inhibitor,Serine Proteinase Inhibitors, Endogenous,Serine Proteinase Inhibitors, Exogenous,Serine Protease Inhibitors, Endogenous,Serine Protease Inhibitors, Exogenous,Antagonist, Serine Proteinase,Endopeptidase Inhibitor, Serine,Inhibitor, Serine Endopeptidase,Inhibitor, Serine Protease,Inhibitor, Serine Proteinase,Protease Inhibitor, Serine,Proteinase Antagonist, Serine,Proteinase Inhibitor, Serine
D015853	Cysteine Proteinase Inhibitors	Exogenous and endogenous compounds which inhibit CYSTEINE ENDOPEPTIDASES.	Acid Cysteine Proteinase Inhibitor,Cysteine Protease Inhibitor,Cysteine Protease Inhibitors,Cysteine Proteinase Antagonist,Cysteine Proteinase Antagonists,Cysteine Proteinase Inhibitor,Cysteine Proteinase Inhibitors, Endogenous,Cysteine Proteinase Inhibitors, Exogenous,alpha-Cysteine Protease Inhibitor,Acid Cysteine Proteinase Inhibitors,alpha-Cysteine Protease Inhibitors,Antagonist, Cysteine Proteinase,Antagonists, Cysteine Proteinase,Inhibitor, Cysteine Protease,Inhibitor, Cysteine Proteinase,Inhibitor, alpha-Cysteine Protease,Inhibitors, Cysteine Protease,Inhibitors, Cysteine Proteinase,Inhibitors, alpha-Cysteine Protease,Protease Inhibitor, Cysteine,Protease Inhibitor, alpha-Cysteine,Protease Inhibitors, Cysteine,Protease Inhibitors, alpha-Cysteine,Proteinase Antagonist, Cysteine,Proteinase Antagonists, Cysteine,Proteinase Inhibitor, Cysteine,Proteinase Inhibitors, Cysteine,alpha Cysteine Protease Inhibitor,alpha Cysteine Protease Inhibitors
D050296	Microbial Viability	Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.	Bacterial Viability,Virus Viability,Bacteria Viability,Microbial Inactivation,Inactivation, Microbial,Viability, Bacteria,Viability, Bacterial,Viability, Microbial,Viability, Virus
D053148	Caspase 3	A short pro-domain caspase that plays an effector role in APOPTOSIS. It is activated by INITIATOR CASPASES such as CASPASE 9. Isoforms of this protein exist due to multiple alternative splicing of its MESSENGER RNA.	CASP3,Apopain,Caspase-3,Pro-Caspase-3,Procaspase-3,Pro Caspase 3,Procaspase 3
D061945	Caspase Inhibitors	Endogenous and exogenous compounds and that either inhibit CASPASES or prevent their activation.	Capase Activation Inhibitors,Caspase Activation Blockers,Caspase Activation Inhibitors,Caspase Blockers,Activation Blockers, Caspase,Activation Inhibitors, Capase,Activation Inhibitors, Caspase,Blockers, Caspase,Blockers, Caspase Activation,Inhibitors, Capase Activation,Inhibitors, Caspase,Inhibitors, Caspase Activation