High throughput, small scale methods to characterise the growth of marine fungi

PLoS One. 2020 Aug 7;15(8):e0236822. doi: 10.1371/journal.pone.0236822. eCollection 2020.

Abstract

Various marine fungi have been shown to produce interesting, bioactive compounds, but scaling up the production of these compounds can be challenging, particularly because little is generally known about how the producing organisms grow. Here we assessed the suitability of using 100-well BioScreen plates or 96-well plates incubated in a robot hotel to cultivate eight filamentous marine fungi, six sporulating and two non-sporulating, to obtain data on growth and substrate (glucose, xylose, galactose or glycerol) utilisation in a high throughput manner. All eight fungi grew in both cultivation systems, but growth was more variable and with more noise in the data in the Cytomat plate hotel than in the BioScreen. Specific growth rates between 0.01 (no added substrate) and 0.07 h-1 were measured for strains growing in the BioScreen and between 0.01 and 0.27 h-1 for strains in the plate hotel. Three strains, Dendryphiella salina LF304, Penicillium chrysogenum KF657 and Penicillium pinophilum LF458, consistently had higher specific growth rates on glucose and xylose in the plate hotel than in the BioScreen, but otherwise results were similar in the two systems. However, because of the noise in data from the plate hotel, the data obtained from it could only be used to distinguish between substrates which did or did not support growth, whereas data from BioScreen also provided information on substrate preference. Glucose was the preferred substrate for all strains, followed by xylose and galactose. Five strains also grew on glycerol. Therefore it was important to minimise the amount of glycerol introduced with the inoculum to avoid misinterpreting the results for growth on poor substrates. We concluded that both systems could provide physiological data with filamentous fungi, provided sufficient replicates are included in the measurements.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ascomycota / drug effects
  • Ascomycota / growth & development*
  • Ascomycota / isolation & purification
  • Culture Media / chemistry
  • Culture Media / pharmacology
  • Glucose / pharmacology
  • Glycerol / pharmacology
  • Penicillium / drug effects
  • Penicillium / growth & development*
  • Penicillium / isolation & purification
  • Seawater / microbiology*
  • Xylose / pharmacology

Substances

  • Culture Media
  • Xylose
  • Glucose
  • Glycerol

Grants and funding

This work was supported by the Academy of Finland (https://www.aka.fi/en/), project No. 289055, Carbohydrate metabolism of marine fungi. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. VTT (with funds from the Academy of Finland) provided support in the form of salaries [AT, DB, SH, MGW] or stipend [PH] for authors, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.