Cyanobacteria are photosynthetic prokaryotes.They exhibit remarkable metabolic adaptability,enabling them to withstand oxidative stress,high salinity,temperature extremes,and UV radiation(UVR).Their adaptive strategie...Cyanobacteria are photosynthetic prokaryotes.They exhibit remarkable metabolic adaptability,enabling them to withstand oxidative stress,high salinity,temperature extremes,and UV radiation(UVR).Their adaptive strategies involve complex regulatory networks that affect gene expression,enzyme activity,and metabolite fluxes to maintain cellular homeostasis.Key stress response systems include the production of antioxidants such as peroxidases(POD),catalase(CAT),and superoxide dismutase(SOD),which detoxify reactive oxygen species(ROS).To withstand environmental stresses,cyanobacteria maintain osmotic balance by accumulating compatible solutes,such as glycine betaine,sucrose,and trehalose.They also adapt to temperature and light fluctuations by modifying membrane properties and regulating photosynthetic activity.Furthermore,secondary metabolites such as mycosporine-like amino acids(MAAs)and scytonemin act as natural UV protectors.This study highlights current advances in understanding these stress tolerance mechanisms,including exopolysaccharide(EPS)formation,compatible solute accumulation,and ROS detoxification.Recent advancements in proteomics and synthetic biology have shed light on novel defense mechanisms,identifying stress-induced proteins and regulatory networks that enhance resilience.This review thoroughly explores the underlyingmolecular and biochemicalmechanisms of cyanobacterial stress tolerance,whichmake thempromising candidates for various biotechnological applications.Future research on cyanobacterial stress adaptation should bring together synthetic biology,omics tools,and environmental biotechnology.Using these approaches together could help create stress-tolerant cyanobacteria with improved use in farming,pollution control,and biofuel production,supporting solutions to global environmental and energy challenges.展开更多
Using Nostoc commune as experiment target,the effect of CO 2 with different concentrations in atmosphere and dosage of UV-B on photosynthetic pigment chlorophyll a （Chl a）,carotenoids,phycoerythrin,phycocyanin,allop...Using Nostoc commune as experiment target,the effect of CO 2 with different concentrations in atmosphere and dosage of UV-B on photosynthetic pigment chlorophyll a （Chl a）,carotenoids,phycoerythrin,phycocyanin,allophycocyanin and UV-B masking materials was studied.The results showed that high dosage of UV-B radiation inhibited the synthesis process of Chl a,phycoerythrin,phycocyanin and allophycocyanin,but promoted the synthesis of carotenoids,MAAs and scytonemin,thus the negative effect produced by UV-B radiation was reduced and the resistance of Nostoc commune against UV-B radiation was enhanced.展开更多
基金supported by the University Grants Commission(UGC),New Delhi,India[Ref.Nos.231620041285,191620014505]the Council of Scientific and Industrial Research(CSIR),New Delhi,India[Ref.Nos.09/0013(12862)/2021-EMR-1,09/0013(16603)/2023-EMR-I,09/0013(21806)/2025-EMR-I]Banaras Hindu University(BHU),India[No.R/Dev./Sch./UGC Non-NET Fello./2022-23/52561].
文摘Cyanobacteria are photosynthetic prokaryotes.They exhibit remarkable metabolic adaptability,enabling them to withstand oxidative stress,high salinity,temperature extremes,and UV radiation(UVR).Their adaptive strategies involve complex regulatory networks that affect gene expression,enzyme activity,and metabolite fluxes to maintain cellular homeostasis.Key stress response systems include the production of antioxidants such as peroxidases(POD),catalase(CAT),and superoxide dismutase(SOD),which detoxify reactive oxygen species(ROS).To withstand environmental stresses,cyanobacteria maintain osmotic balance by accumulating compatible solutes,such as glycine betaine,sucrose,and trehalose.They also adapt to temperature and light fluctuations by modifying membrane properties and regulating photosynthetic activity.Furthermore,secondary metabolites such as mycosporine-like amino acids(MAAs)and scytonemin act as natural UV protectors.This study highlights current advances in understanding these stress tolerance mechanisms,including exopolysaccharide(EPS)formation,compatible solute accumulation,and ROS detoxification.Recent advancements in proteomics and synthetic biology have shed light on novel defense mechanisms,identifying stress-induced proteins and regulatory networks that enhance resilience.This review thoroughly explores the underlyingmolecular and biochemicalmechanisms of cyanobacterial stress tolerance,whichmake thempromising candidates for various biotechnological applications.Future research on cyanobacterial stress adaptation should bring together synthetic biology,omics tools,and environmental biotechnology.Using these approaches together could help create stress-tolerant cyanobacteria with improved use in farming,pollution control,and biofuel production,supporting solutions to global environmental and energy challenges.
基金Supported by the National Natural Science Foundation of China(30700084)
文摘Using Nostoc commune as experiment target,the effect of CO 2 with different concentrations in atmosphere and dosage of UV-B on photosynthetic pigment chlorophyll a （Chl a）,carotenoids,phycoerythrin,phycocyanin,allophycocyanin and UV-B masking materials was studied.The results showed that high dosage of UV-B radiation inhibited the synthesis process of Chl a,phycoerythrin,phycocyanin and allophycocyanin,but promoted the synthesis of carotenoids,MAAs and scytonemin,thus the negative effect produced by UV-B radiation was reduced and the resistance of Nostoc commune against UV-B radiation was enhanced.
