Studies on the injury and reactivation of Escherichia coli under ultraviolet disinfection
XU Li-mei, XU Peng-cheng, ZHANG Chong-miao, WANG Xiao-chang
Key Laboratory of Northwest Water Resource, Environment and Ecology, Department of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
In this study,the photoreactivation and dark repair of Escherichia coli (E.coli) was investigated.The effects of ultraviolet (UV) disinfection on membrane integrity,adenosine triphosphate (ATP) and nucleic acid (DNA,RNA) were further analyzed.The aim of our study was to explore the response pattern of E.coli to UV disinfection by combination of SOS response mechanism of recA gene.The results showed that the inactivation efficiency of E.coli reached 5.63-log at a UV dose of 20mJ/cm2.When the light exposure time and dark repair time was prolonged to 24h after a UV dose of 20mJ/cm2,the percentages of photoreactivation and dark repair observed for E.coli were 0.018% and 0.00042%,respectively.The ability of photoreactivation of E.coli was higher than that of dark repair.The DNA damage depended on the fragment length of genes during UV disinfection.The longer the 16s rRNA gene was,the more seriously damage occurred.Conventional UV doses in wastewater treatment did not affect the amount of total ATP and membrane integrity,which provided basic guarantee for the reactivation of E.coli after UV disinfection.UV disinfection caused serious damage in recA RNA.When UV dose reached 50mJ/cm2,E.coli lost the SOS response mechanism.Hence,little reactivation was observed using the culture method at a UV dose of 80mJ/cm2.The lost of recA RNA could be used as an indicator for the occurrence of the irreversible injury to microorganism.
徐丽梅, 许鹏程, 张崇淼, 王晓昌. 紫外线消毒对大肠杆菌的损伤及复苏的研究[J]. 中国环境科学, 2017, 37(7): 2639-2645.
XU Li-mei, XU Peng-cheng, ZHANG Chong-miao, WANG Xiao-chang. Studies on the injury and reactivation of Escherichia coli under ultraviolet disinfection. CHINA ENVIRONMENTAL SCIENCECE, 2017, 37(7): 2639-2645.
Shin G A, Linden K G, Sobsey M D. Low pressure ultraviolet inactivation of pathogenic enteric viruses and bacteriophages[J]. Journal of Environmental Engineering and Science, 2005,4(S1):S7-S11.
Locas A, Demers J, Paymenta P. Evaluation of photoreactivation of Escherichia coli and enterococci after UV disinfection of municipal wastewater[J]. Canadian Journal of Microbiology, 2008,54(11):971-975.
[5]
Kerim K, Örmeci B. Regrowth potential of bacteria after ultraviolet disinfection in the absence of light and dark repair[J]. Journal of Environmental Engineering, 2014,141(3):04014069-1-7.
[6]
Lin Y W, Li D, Gu A Z, et al. Bacterial regrowth in water reclamation and distribution systems revealed by viable bacterial detection assays[J]. Chemosphere, 2015,144(5):2165-2174.
Oguma K, Katayama H, Mitani H, et al. Determination of pyrimidine dimers in Escherichia coli and Cryptosporidium parvum during UV light inactivation, photoreactivation, and dark repair[J]. Applied & Environmental Microbiology, 2001,67(10):4630-4637.
Guerineau H, Dorner S, Carriere A, et al. Source tracking of leaky sewers:a novel approach combining fecal indicators in water and sediments[J]. Water research, 2014,58:50-61.
[11]
Edberg S C, Rice E W, Karlin R J, et al. Escherichia coli:the best biological drinking water indicator for public health protection[J]. Journal of Applied Microbiology, 2000,88(s1):106s-116s.
[12]
严敏,高乃云.紫外线消毒在给水处理中的应用[J]. 给水排水, 2004,30(9):8-12.
[13]
Ren Z C, Craik S A, Bolton J R. Comparison of the action spectra and relative DNA absorbance spectra of microorganisms:Information important for the determination of germicidal fluence (UV dose) in an ultraviolet disinfection of water[J]. Water Research, 2009,43(20):5087-5096.
[14]
Tomlins R I, Ordal Z J. Precursor ribosomal ribonucleic acid and ribosome accumulation in vivo during the recovery of Salmonella typhimurium from thermal injury[J]. Journal of Bacteriology, 1971,107(1):134-142.
[15]
Lim E S, Le T H, Lee S H, et al. Stress responses analysis of As(Ⅲ), Cd and Pb in Escherichia coli[J]. Toxicology and Environmental Health Sciences, 2009,1(3):192-195.
[16]
Jungfer C, Schwartz T, Obst U. UV-induced dark repair mechanisms in bacteria associated with drinking water[J]. Water Research, 2007,41(1):188-196.
[17]
Kollu K, Örmeci B. UV-induced self-aggregation of E. coli after low and medium pressure ultraviolet irradiation[J]. Journal of Photochemistry and Photobiology B:Biology, 2015,148:310-321.
[18]
NSF guide to the European standards for drinking water treatment units[S]. NSF International, 2009.
Guo M T, Huang J J, Hu H Y, et al. Growth and repair potential of three species of bacteria in reclaimed wastewater after UV disinfection[J]. Biomedical & Environmental Sciences, 2011, 24(4):400-407.
[22]
Cho M, Kim J, Kim J Y, et al. Mechanisms of Escherichia coli inactivation by several disinfectants[J]. Water Research, 2010, 44(11):3410-3418.
Hammes F, Goldschmidt F, Vital M, et al. Measurement and interpretation of microbial adenosine tri-phosphate (ATP) in aquatic environments[J]. Water Research, 2010,44(13):3915-3923.
[25]
Pharand L, Dyke M I V, Anderson W B, et al. Assessment of biomass in drinking water biofilters by adenosine triphosphate[J]. JournalAmerican Water Works Association, 2014,106(10):E433-E444.
[26]
Trombert A, Irazoqui H, Martín C, et al. Evaluation of UV-C induced changes in Escherichia coli DNA using repetitive extragenic palindromic-polymerase chain reaction (REP-PCR)[J]. Journal of Photochemistry & Photobiology B Biology, 2007,89(1):44-49.
