Ghosh Suchismita, Ayayee Paul A, Valverde-Barrantes Oscar J, Blackwood Christopher B, Royer Todd V, Leff Laura G
Department of Biological Sciences, Kent State University, Kent, OH, 44242, USA.
International Center for Tropical Botany (ICTB), Florida International University, Miami, FL, 33199, USA.
BMC Microbiol. 2017 Apr 4;17(1):87. doi: 10.1186/s12866-017-0993-7.
The nitrogen (N) cycle consists of complex microbe-mediated transformations driven by a variety of factors, including diversity and concentrations of N compounds. In this study, we examined taxonomic diversity and N substrate utilization by heterotrophic bacteria isolated from streams under complex and simple N-enrichment conditions.
Diversity estimates differed among isolates from the enrichments, but no significant composition were detected. Substrate utilization and substrate range of bacterial assemblages differed within and among enrichments types, and not simply between simple and complex N-enrichments.
N substrate use patterns differed between isolates from some complex and simple N-enrichments while others were unexpectedly similar. Taxonomic composition of isolates did not differ among enrichments and was unrelated to N use suggesting strong functional redundancy. Ultimately, our results imply that the available N pool influences physiology and selects for bacteria with various abilities that are unrelated to their taxonomic affiliation.
氮（N）循环由多种因素驱动的复杂微生物介导的转化过程组成，这些因素包括氮化合物的多样性和浓度。在本研究中，我们检测了在复杂和简单氮富集条件下从溪流中分离出的异养细菌的分类多样性和氮底物利用情况。
富集培养物中的分离株多样性估计值不同，但未检测到显著的组成差异。细菌群落的底物利用和底物范围在富集类型内部和之间存在差异，而不仅仅是在简单和复杂氮富集之间。
一些复杂和简单氮富集培养物中的分离株之间的氮底物使用模式不同，而其他一些则出人意料地相似。分离株的分类组成在富集培养物之间没有差异，并且与氮利用无关，这表明存在很强的功能冗余。最终，我们的结果表明，可用的氮库会影响生理学，并选择具有各种能力的细菌，这些能力与其分类归属无关。
