Structure and function of bacterial communities emerging from different sources under identical conditions

Area of Science:

• Microbiology
• Ecology
• Environmental Science

Background:

• Bacterial community composition (BCC) is influenced by local environmental conditions and metacommunity processes.
• Understanding the drivers of BCC is crucial for ecological and environmental studies.

Purpose of the Study:

• To compare the roles of local environmental conditions versus metacommunity processes in determining bacterial community composition.
• To investigate if bacterial communities regrown under identical conditions converge or maintain historical differences.

Main Methods:

• A batch culture experiment regrew bacteria from eight diverse aquatic habitats under uniform conditions.
• Terminal restriction fragment length polymorphism (TFLP) analysis of the 16S rRNA gene was used to assess community composition.
• Enzyme activities, biomass production, and respiration were measured to evaluate community functions.

Main Results:

• Bacterial communities regrown under identical conditions showed significant differences, reflecting their original inoculum composition.
• No increase in community similarity was observed compared to communities grown in their native habitats.
• Specific functions varied between communities, but broad-scale functions like biomass production remained similar.

Conclusions:

• Historical and distributional factors of source communities are stronger determinants of bacterial community composition than local environmental conditions.
• Bacterial communities exhibit resilience in broad-scale functions despite divergence in specific composition and functions.