Metabolomic and Genomic Analysis of Bioactive Compounds of Phacidium infestans Karsten DSM 5139 Cultivated on Pinus sylvestris Needles

TL;DR

This study explores how a cold-adapted fungus, Phacidium infestans, breaks down pine needles and uses their nutrients despite their antimicrobial properties.

Contribution

The study reveals novel metabolic and genomic strategies used by Phacidium infestans to survive and thrive on pine needles.

Findings

DI-HRMS identified 112 compounds in needle samples, showing increased terpenoids from resin ducts after fungal cultivation.

P. infestans consumed antifungal compounds like taxiresinol and salicylic acid, with high CTR/SA ratios.

Genomic analysis revealed 421 secreted proteins, including enzymes and efflux pumps, aiding in host penetration and detoxification.

Abstract

This study investigates how Phacidium infestans acquires nutrients on
Pinus sylvestris
needles, which possess antimicrobial properties.
P. infestans
was evaluated for its growth and enzyme production on various substrates, alongside genomic and metabolomic analysis. Direct‐infusion high‐resolution mass spectrometry (DI‐HRMS) was performed on methanol extracts obtained from
P. infestans
cultivated on needles and malt extract media. DI‐HRMS analysis identified 21 compounds from the malt extract and 112 from the needle samples. The resin components increased in the needle samples post‐cultivation, suggesting terpenoid release from resin ducts due to fungal degradation of plant cell walls.
P. infestans
fully consumed sugars and antifungal compounds, including taxiresinol and salicylic acid, with control‐to‐sample ratios (CTR/SA) of 289.76 and 47.24, respectively. Moreover, lariciresinol and pinoresinol were reduced to undetectable levels. The genomic analysis identified 421 secreted proteins, including 128 carbohydrate‐active enzymes, 3 cutinases, and 49 lipases that aid host penetration and wax degradation. Several multi‐drug efflux pumps and two acyclic terpene utilisation proteins were identified as well. These proteins support the cellular integrity of
P. infestans
by expelling toxic compounds. Our findings provide valuable insights into the metabolic strategies of
P. infestans
for nutrient assimilation on pine needles.

Phacidium infestans DSM 5139 was studied for its ability to penetrate pine needles and overcome their inhibitory compounds. Using mass spectrometry and genome mining, we identified the biological and molecular strategies enabling nutrient acquisition and resilience against chemical stress, providing insights into the survival mechanisms of this cold‐adapted fungal pathogen.

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