Phosphorus starvation response genes and function coupling: A mechanism to regulate phosphorus availability in a...

Area of Science:

• Environmental Microbiology
• Biogeochemistry
• Estuarine Ecology

Background:

• Phosphorus (P) is crucial for estuarine primary production, but microbial P-cycling gene composition and adaptation mechanisms are poorly understood.
• Estuaries face challenges in managing phosphorus availability and its impact on ecosystem health.

Purpose of the Study:

• To investigate the relationship between P-cycling functional genes, microbial interactions, and P availability in the Jiulong River Estuary.
• To elucidate the effects of environmental factors, particularly salinity and temperature, on microbial P-cycling functions.

Main Methods:

• Coupled 16S rDNA and metagenomics sequencing to analyze microbial communities and functional genes.
• Statistical analysis to determine the influence of environmental variables on P-cycling genes and functions.

Main Results:

• P-cycling gene abundance varied seasonally (highest in winter, lowest in summer) and spatially (higher riverward than seaward).
• Salinity significantly affected P-cycling functions, with negative impacts on inorganic P-solubilization, organic P-mineralization, and P uptake/transport, but a positive effect on P-starvation response regulation.
• P-starvation response regulation (PR) and P uptake/transport (PT) genes were key predictors of soluble reactive phosphorus (SRP) concentrations.

Conclusions:

• Salinity and microbial communities regulate estuarine SRP by modulating P-cycling functions and gene expression.
• P-starvation response regulation (PR) and P uptake/transport (PT) are critical functional genes for predicting SRP variations.
• Findings enhance understanding of microbial P-cycling and inform eutrophication management strategies in estuaries.