Marker Guide

Mucin degrading microbes

What this marker measures

The collective capacity of the microbial community to degrade mucin, the glycoproteins that help form the protective mucus layer lining the gut. Some mucin degradation is normal and may support microbial cross-feeding, but elevated mucin-degrading potential may contribute to mucus layer thinning, reduced gut barrier integrity, and intestinal inflammation, particularly when dietary fibre intake is low^1–3.

Clinical associations

Consider this marker when your patient presents with:

Gut barrier concerns

Suspected increased intestinal permeability, mucus layer disruption, or impaired gut barrier function

GI symptoms

Diarrhoea, loose stools, abdominal pain, urgency.

Intestinal inflammation and mucosal health

IBD-type presentation, elevated calprotectin, or chronic intestinal inflammation where mucus barrier disruption may be relevant.

Interpreting the result

All results are compared to Microba's healthy cohort to determine whether they fall within or outside the expected range.

LOW

Mucin-degrading potential is lower than expected

This result does not suggest excess microbial pressure on the mucus layer.No intervention needed for this marker.

Within Range

Mucin-degrading potential is within expected parameters

This suggests mucin degradation is not elevated and is unlikely to be compromising the mucus barrier.

HIGH

Mucin-degrading potential is higher than expected

May indicate increased pressure on the mucus layer and may be relevant in intestinal inflammation, impaired mucus barrier integrity . Action: see patient management insights below

Patient management insights

Reduce excess mucin-degrading potential and support mucus layer and gut barrier integrity.

Dietary strategies

A high fibre diet may reduce mucin-degrading microbes^4,5GRADE D

Tips for patients discussion

Your report shows elevated levels of microbes that can use the gut’s protective mucus layer as a food source. This layer acts as a first line of defence for your intestinal wall. Increasing tolerated dietary fibre can help shift microbial activity toward fibre fermentation and support gut barrier integrity

The community

No single species produces butyrate alone — here are some of the most common, however this list is not exhaustive

Agathobacter faecis
Alistipes obesi
Alistipes onderdonkii
Alistipes shahii
Bacteroides caccae
Bacteroides ovatus
Bacteroides thetaiotaomicron
Bacteroides uniformis
Bacteroides_B vulgatus
Blautia_A sp900066165
CAG-41 sp900066215
Barnesiella intestinihominis
CAG-56 sp900066615
Odoribacter splanchnicus
Roseburia hominis
Fusicatenibacter saccharivorans
GCA-900066135 MIC6659
Roseburia inulinivorans
Ruminococcus_A sp003011855
KLE1615 sp900066985
Parabacteroides distasonis
Bacteroides_B dorei
Parabacteroides merdae
UBA7160 MIC9207

How results are calculated

All microbiome marker results are compared against the Microba Healthy Cohort — a purpose-built reference group of more than 450 healthy individuals, collected and analysed using the same workflow as patient samples.

Each marker is scored by comparing the patient's relative abundance against the cohort average. The distance from this average is expressed as standard deviations, and determines whether a result is classified as Low, Borderline, or High.

How the result scale works

▲ AVG (Healthy Cohort average)

The patient's relative abundance is compared to the Healthy Cohort average. A negative distance from average means the microbial group is less abundant than the Healthy Cohort. A positive distance means it is more abundant. Results falling outside the expected range are classified as borderline or high/low (borderline high/low:+/-0.68,andhigh/low:+/-1.28).

Evidence grading for patient management insights

The letter grades shown next to each patient management insight show the quality of the research behind it. Every insight provided has been through a rigorous review of the scientific literature and graded using the NHMRC Levels of Evidence, so you can see exactly how strong the evidence is before applying it in practice.

Source references for all clinical associations, interpretation definitions, and patient management insights on this card.

1. Blecksmith, S. E., Oliver, A., Alkan, Z. & Lemay, D. G. Gut Microbiome Genes Involved in Plant and Mucin Breakdown Correlate with Diet and Gastrointestinal Inflammation in Healthy United States Adults. The Journal of Nutrition 155, 3757–3768 (2025).
2. Desai, M. S. et al. A Dietary Fiber-Deprived Gut Microbiota Degrades the Colonic Mucus Barrier and Enhances Pathogen Susceptibility. Cell 167, 1339-1353.e21 (2016).
3. Earle, K. A. et al. Quantitative Imaging of Gut Microbiota Spatial Organization. Cell Host & Microbe 18, 478–488 (2015).
4. Pan, S. et al. Gut Microbial Protein Expression in Response to Dietary Patterns in a Controlled Feeding Study: A Metaproteomic Approach. Microorganisms 8, 379 (2020).
5. Dirks, B. et al. Microbial Feast or Famine: dietary carbohydrate composition and gut microbiota metabolic function. bioRxiv 2025.10.27.684932 (2025) doi:10.1101/2025.10.27.684932.