Department of Environmental Engineering, College of Environmental and Resource Sciences, Zhejiang University, Yuhangtang Road 866#, Hangzhou, 310058, Peoples' Republic of China.
World J Microbiol Biotechnol. 2013 Dec;29(12):2213-8. doi: 10.1007/s11274-013-1390-5. Epub 2013 Jun 4.
A conventional plate count is the most commonly employed method to estimate the number of living bacteria in environmental samples. In fact, judging the level of viable culture by plate count is limited, because it is often several orders of magnitude less than the number of living bacteria actually present. Most of the bacteria are in "viable but non-culturable" (VBNC) state, whose cells are intact and alive and can resuscitate when surrounding conditions are more favorable. The most exciting recent development in resuscitating VBNC bacteria is a bacterial cytokine, namely, the resuscitation-promoting factor (Rpf), secreted by Micrococcus luteus, which promotes the resuscitation and growth of high G+C Gram-positive organisms, including some species of the genus Mycobacterium. However, most of studies deal with VBNC bacteria only from the point of view of medicine and epidemiology. It is therefore of great significance to research whether these VBNC state bacteria also possess some useful environmental capabilities, such as degradation, flocculation, etc. Further studies are needed to elucidate the possible environmental role of the VBNC bacteria, rather than only considering their role as potential pathogens from the point view of epidemiology and public health. We have studied the resuscitation of these VBNC bacteria in polluted environments by adding culture supernatant containing Rpf from M. luteus, and it was found that, as a huge microbial resource, VBNC bacteria could provide important answers to dealing with existing problems of environmental pollution. This mini-review will provide new insight for considering the potentially environmental functions of VBNC bacteria.
传统平板计数法是最常用于估计环境样品中活菌数量的方法。事实上，通过平板计数来判断可培养物的水平是有限的，因为它通常比实际存在的活菌数量少几个数量级。大多数细菌处于“存活但不可培养”（VBNC）状态，其细胞完整且存活，当周围条件更加有利时可以复苏。最近在复苏 VBNC 细菌方面最令人兴奋的进展是细菌细胞因子，即微球菌分泌的促复苏因子（Rpf），它促进高 G+C 革兰氏阳性菌的复苏和生长，包括分枝杆菌属的一些种。然而，大多数研究仅从医学和流行病学的角度来研究 VBNC 细菌。因此，研究这些 VBNC 状态的细菌是否具有一些有用的环境能力，如降解、絮凝等，具有重要意义。需要进一步研究来阐明 VBNC 细菌的可能环境作用，而不仅仅是从流行病学和公共卫生的角度考虑它们作为潜在病原体的作用。我们通过添加来自 M. luteus 的含有 Rpf 的培养上清液来研究污染环境中这些 VBNC 细菌的复苏，结果发现，作为巨大的微生物资源，VBNC 细菌可以为处理现有的环境污染问题提供重要答案。这篇综述将为考虑 VBNC 细菌的潜在环境功能提供新的视角。
