Mortierella

Mortierella is a genus of soil-dwelling fungi in the phylum Mortierellomycota (formerly placed in Zygomycota). While primarily known as environmental saprotrophs, Mortierella species have recently been identified as residents of the human gut mycobiome — the fungal component of the intestinal microbiota. Their presence in the gut is increasingly recognized as a marker of metabolic and cardiovascular health.

What makes Mortierella remarkable in the WikiBiome context is its emerging role as a protective fungal marker. Unlike Candida and Malassezia, which consistently expand in cardiometabolic disease, Mortierella is depleted in hypertension and prehypertension, positioning it as the mycobiome's counterpart to bacterial health indicators like faecalibacterium prausnitzii.

Metal Dependencies

  • Zinc: Mortierella species require zinc for their lipid metabolism enzymes, particularly the desaturases and elongases involved in polyunsaturated fatty acid (PUFA) synthesis.
  • Iron: Required for cytochrome-dependent oxidative metabolism.

The genus is notable in industrial biotechnology for its ability to produce arachidonic acid (ARA, 20:4 omega-6) and other long-chain PUFAs. Mortierella alpina is used commercially for ARA production. Whether gut-resident Mortierella produces biologically significant PUFA quantities remains to be determined.

Key Enzymes and Virulence Factors

Mortierella has no known virulence factors. Its enzymatic profile reflects a saprophytic, lipid-producing metabolism:

  • Delta-6-desaturase and elongase: Key enzymes in the PUFA synthesis pathway. These convert linoleic acid through gamma-linolenic acid to dihomo-gamma-linolenic acid and ultimately arachidonic acid.
  • Lipase activity: Enables breakdown of complex lipids in the gut environment.

Ecological Role

In the gut mycobiome, Mortierella appears to play a stabilizing role:

  • Depletion precedes disease: Mortierella was depleted in both prehypertension and hypertension states compared to normotensive controls, and its depletion was present even before clinical hypertension developed. This temporal pattern suggests Mortierella loss is an early event in cardiometabolic disease progression, not a consequence (zou 2022 mycobiome hypertension immunoglobulin, cross-sectional).
  • Immunomodulatory associations: Mortierella abundance was positively associated with serum immunoglobulin light chain (LC) lambda concentrations, suggesting it interacts with the immune system in ways that differ from pathogenic fungi like malassezia, which was positively correlated with both LC kappa and lambda (zou 2022 mycobiome hypertension immunoglobulin, cross-sectional).
  • PCOS-BMI interaction: In PCOS, Mortierella showed a striking BMI-dependent pattern: elevated in overweight PCOS patients (PCOS-HB) but not in normal-BMI PCOS. It negatively correlated with BMI but adversely correlated with LH, androstenedione, total testosterone, HDL-C, and DHEA, flagging it as a marker of metabolic-reproductive decoupling (yin 2022 pcos bacteriome mycobiome metabolome bmi, cross-sectional, n=88).
  • Cardiometabolic progression: A comprehensive review identified Mortierella as potentially protective in hypertension alongside evidence that Malassezia and Candida are consistently pathology-associated (wei 2025 gut mycobiome cardiometabolic progression, expert-opinion).

Conditions Associated

Depleted in:

Enriched in:

  • PCOS (overweight subgroup): Uniquely elevated in overweight PCOS patients (PCOS-HB). This is the first study to demonstrate that fungal dysbiosis in PCOS is BMI-dependent. The enrichment may reflect metabolic substrate availability in overweight but metabolically active individuals (yin 2022 pcos bacteriome mycobiome metabolome bmi, cross-sectional, n=88).

Key Studies

StudyFindingEvidence Level
zou 2022 mycobiome hypertension immunoglobulinDepleted in pre-HTN and HTN; positive LC lambda associationCross-sectional
yin 2022 pcos bacteriome mycobiome metabolome bmiBMI-dependent enrichment in overweight PCOS; metabolic-reproductive decouplerCross-sectional
wei 2025 gut mycobiome cardiometabolic progressionProtective in hypertension; contrasts with Candida/Malassezia pathologyExpert opinion

Cross-References