Optimal Microbiome Networks: Macroecology and Criticality

Area of Science:

• Microbiome research
• Network inference
• Systems biology

Background:

• The human microbiome is a complex ecosystem.
• Irritable Bowel Syndrome (IBS) is a prevalent functional gastrointestinal disorder.
• Understanding microbiome complexity is crucial for IBS.

Purpose of the Study:

• To untangle human microbiome complexity in IBS.
• To identify differences in species interaction networks between healthy and unhealthy individuals.
• To explore macroecological characteristics of the microbiome.

Main Methods:

• Novel information theoretic network inference model.
• Analysis of species interaction networks.
• Macroecological characterization of the microbiome.

Main Results:

• Healthy and unhealthy microbiome networks differ structurally and functionally.
• Healthy networks exhibit neutral, scale-free topology; unhealthy networks are random.
• An inverse relationship exists between species interactivity and relative abundance (RSA).
• Healthy microbiomes show high diversity growth rate, low turnover, and stable RSA.
• Microbiome criticality is not necessarily at the healthy-unhealthy phase transition.

Conclusions:

• Network hubs should be defined by information flow, not just node degree.
• Macroecological characterization aids public health and disease diagnosis.
• Species-specific analyses can inform personalized pre- and probiotic treatments.