Introduce of Viable But Nonculturable Bacteria

Document Type : Research Paper

Authors

1 Ph.D Student of Microbiology, Isfahan University

2 Professor of Biology, Faculty of Science, Isfahan University

Abstract

Viable-But-Nonculturable-State (VBNC) is the condition in which bacteria fail to grow on their routine bacteriological media where they would normally grow and develop into colonies, but are still alive and capable of renewed metabolic activity. VBNC state is useful for evaluating public health and for ascertaining the sterility of drinking water, pharmaceuticals, and foodstuff. A number of bacteria, mostly pathogenic to humans, have been proved to enter into this state in response to natural stresses such as starvation, incubation out of optimum growth temperature, increased osmotic pressure, etc. Once in the VBNC state, they undergo various physiological, structural, and genetic alterations. These alterations result in reduced cell size, conversion from bacilli to coccid, thickened cell walls, and peptidoglycan gaining many cross links. Metabolic changes also occur that include reductions in growth, nutrient transport, and respiratory rate; biosynthesis of new protein, and ATP remaining at a constant level. It has been shown that in the VBNC state, some pathogens conserve their virulence properties. Gene expression continues in the VBNC cell. Nucleic acids remain intact in the early VBNC phase but they gradually undergo degradation with prolonged VBNC. Cytological methods such as direct viable count and reduction of tetrazolium salts, and molecular methods such as reverse transcription polymerase chain reaction and green fluorescent protein have been used for the study of VBNC. Resuscitation from VBNC state starts when the inducing factor(s) is/are lifted. Factors that help the resuscitation of VBNC bacteria include addition of certain nutrients and chemicals, introduction of a few culturable cells into the VBNC cell population, and passage through the animal host. As virulence properties are sustained during the VBNC phase, special care must be paid when evaluating sterility of drinking water.

Keywords


1- Chowdhury, M. A. R., Ravel, J., and Hill, R. T. (2004). “Physiology and molecular genetics of viable but non-culturable microorganisms.” Applied and Environmental Microbiology, 52, 111-128.
2- Neil, J. R. (2004). “Viable but nonculturable forms of food and waterborne bacteria.” Trends in Food Science & Technology, 15, 462–467.
3- Norma, B., and Marcela, C. C. (2004). “Viable but nonculturable Vibrio cholerae O1 in the aquatic environment of argentina.” Applied and Environmental Microbiology, 70, 7481–7486
4- James, D. O., and Lena, N. (1991). “Formation of nonculturable Vibrio vulnificus cells and its relationship to the starvation state.” Applied and Environmental Microbiology, 57, 2640-2644.
5- Daniel, T., and Jacobson, V. C. (2005). “Molecular analysis of VBNC response.” J. of Microbiology, 23, 123-150.
6- کسری کرمانشاهی، ر.، پور مقدس، ح.، و میر خان، آ. (1380). بررسی ارتباط بین آلودگی میکربی و عوامل فیزیکی و شیمیایی (دما و BOD) در بخشی از آب زاینده رود در فصول مختلف سال. م. آب و فاضلاب، 38، 16-22.
7- Valérie, B., Michel F., Eric D., and Florence, J. (2002). “Environmental and physico-chemical factors induce VBNC state in Listeria monocytogenes.” Vet. Res., 33, 359–370.
8- Mark, D. W. and James, D. O. (1997). “Resuscitation of Vibrio vulnificus from the viable but nonculturable state.” Applied and Environmental Microbiology, 63, 1002–1005.
9- LleoÁ, M. M., Bonato, B., and Signoretto, M. (2001). “Resuscitation rate in different enterococcal species in the viable but non-culturable state.” J. of Applied Microbiology, 52, 91-102.
10- Yamamato, H. (2000). “Viable but non culturable state as a general phenomenon of non-spore forming bacteria and its modeling.” J. of Infection and Chemotgherapy, 6 (2), 112-114.
11- Rice, S. A., Mc Dougald, D., and Kjelleberg, S. (2000). “Vibrio vulnificus: a physiological and genetic approach to the viable but non culturable state.” The J. of Infection Disease, 6, 115-120.
12- Besnard, V., Federighi, M. Cappelier, J. M. )2000(.“Development of a direct viable count procedure for the investigation of VBNC state in Listeria monocytogenes.” Lett. Appl. Microbiol., 31, 77–81.
13- Tholozan, L., Cappelier, J. M., and Tissier, J. P. (1999). “Physiological characterization of viable-but-nonculturable Campylobacter jejuni cells.” Applied and Environmental Microbiology, 65, 1110–1116.
14- Cappelier, J. M. C., Magras, J. L., and Federighi, M.(1999). “Recovery of viable but non-culturable Campylobacter jejuni cells in two animal models.” Food Microbiology, 16, 375-383.
15- Srilekha, D., Jennifer, V., Sophie, D. (2006). “Chlamydia trachomatis enters a viable but noncultivable state within herpes simplex virus type 2 co-infected host cells.” Cellular Microbiology, 1, 149–162.
16- Brian, g., and Todd, R.) 2001(.“Concentrations of copper thought to be toxic to Escherichia coli can induce the viable but nonculturable condition.” Applied and Environmental Microbiology, 67, 5325–5327.
17- Federighi, M., and Tholozan, J. M. (1998). “Evidence of non-coccoid viable but non-culturable Campylobacter jejuni cells in microcosmwater by direct viable count, CTC-DAPI double staining, and scanning electron microscopy.” Food Microbiology, 15, 539-550.
18- Ishra, R. M., and  Shahamat, M. A. R. (1996). “Potential virulence of viable but nonculturable Shigella dysenteriae type 1.” Applied and Environmental Microbiology, 62, 115–120.
19- Caterina, S., Maria, D.,  Maria, C., and Pietro, C. (2000). “Cell wall chemical composition of Enterococcus faecalis in the viable but nonculturable state.” Applied and Environmental Microbiology, 66, 1953–1959.
20- Oliver, J. D. (1999). “The viable but nonculturable state and cellular resuscitation.” Microbial. Biosystems, 24, 85-95.
21- Douglas, B., Arseny, K., and Kaprelyants, D. H. (1998). “Viability and activity in readily culturable bacteria  a review and discussion of the practical issues.” Antonie van Leeuwenhoek, 73, 169–187.
22- Tamara, G., and Armisen, P. S. (2004). “Enumeration of viable E. coli in rivers and wastewaters by fluorescent in situ hybridization.” J. of Microbiological Methods, 58, 269-279.
23- کسری کرمانشاهی، ر.، و غزالی، م. ن. (1372). جداسازی، تشخیص و تغییرات فصلی باکتری‌ها در زاینده رود اصفهان. م. علمی و پژوهشی دانشگاه اصفهان،  ج 1و2 علوم پایه، 134-176.
24- Oliver, D. J. (2005). “The viable but nonculturable state in bacteria.” J. of Microbiology, 43, 93-100.
25- Patricia, P., Yolanda, M., and Jose, L. A. (2006). “A combination of direct viable count and fluorescent in situ hybridization for estimating Helicobacter pylori cell viability.” Research in Microbiology, 157, 345–349.
26- Diane, M., Scott, A., Dieter, W., and Sta¡an, K. (1998). “Nonculturability: adaptation or debilitation.?” FEMS Microbiology Ecology, 25, 1-9.
27- Yogita, N. S. (2005).  “Viable but non-culturable bacteria their impact on public health.” Current Science, 89, 10-12.
28- Ishrat, R. Shahamat, P. A., Kirchman, Russekcohen, E., and colwell,  R. R. (1994). “Methionine uptake and cytopathogenicity of viable but nonculturable Shigella dysenteriae Type 1.” Applied and Environmental Microbiology, 60, 3573-3579.
29- Rowe, M., Dunstall, T. G. R., Kirk C. F., and Loughney, J. L. (1998). “Development of an image system for the study of viable but non-culturable forms of Campylobacter jejuni and its use to determine their resistance to disinfectants.” Food Microbiology, 15, 491-498.
30- Jang, C., and Sang-Jong, K. (1999). “Green fluorescent protein-based direct viable count to verify a viable but non-culturable state of Salmonella thyphi in environmental samples.” J. of Microbiological Methods, 36, 227-235.
31- Jeffrey, J. B., Xu, H., and Ritam, R. C.(1991). “Viable but nonculturable bacteria in drinking water.” Applied and Environmental Microbiology, 57, 875-878.
32- Bogosian, G., and Edward, V. B. )2001(. A matter of bacteria life and death, EMBO report. 21, 770-771.
33- Valérie, B., Michel, F., and Eric, V. (2002). “Environmental and physico-chemical factors induce VBNC state in Sallmoella thyphi.” Vet. Res., 35,  250-270.