Quorum sensing for improved production of industrially useful products from filamentous fungi
type: CreativeWork
description: Quorum sensing (QS) is a cell density dependant phenomena utilized as a communication process among microorganisms to regulate their physiological responses. QS depends on the production and release of low molecular weight, diffusible chemical signalling molecules, known as quorum sensing molecules (QSM) in the extracellular milieu. When the concentrations of the QSMs reach a critical threshold corresponding to a particular cell density, they bind to a receptor enabling them to function as transcriptional regulators. QS is widely studied in Gram-positive and Gram-negative bacteria in addition to unicellular fungi. Various recent studies report the presence of QS in filamentous fungi. Lipophilic molecules, including lactone-based molecules and the oxygenated poly-unsaturated fatty acids, oxylipins, are the major signalling molecules reported in filamentous fungi. This study correlates the cell-densities of filamentous fungi to the regulation of their different physiological responses. Two fungal species have been investigated. The first is Penicillium sclerotiorum. It was found that addition of ethyl acetate extracts from high cell densities of P. sclerotiorum culture increases sporulation delays the onset of hyphal branching and enhances the production of the secondary metabolite, sclerotiorin in shaken flasks as well as stirred tank bioreactors (STR). GC-MS analysis of the high cell-density extracts revealed several molecules including the oxylipin ricinoleic acid that might be involved in the regulation of the P. sclerotiorum physiological responses via QS. The second species studied was Aspergillus terreus. Here, the role of oxylipins as signalling molecules was investigated. It was found that the supplementation of linoleic acid, as an oxylipin precursor, enhances the production of the secondary metabolite lovastatin in shaken flasks and STRs. Studies using linoleic acid were extended, to investigate its effect on the cytosolic proteome profile of A. terreus. Re…
abstract: Quorum sensing (QS) is a cell density dependant phenomena utilized as a communication process among microorganisms to regulate their physiological responses. QS depends on the production and release of low molecular weight, diffusible chemical signalling molecules, known as quorum sensing molecules (QSM) in the extracellular milieu. When the concentrations of the QSMs reach a critical threshold corresponding to a particular cell density, they bind to a receptor enabling them to function as transcriptional regulators. QS is widely studied in Gram-positive and Gram-negative bacteria in addition to unicellular fungi. Various recent studies report the presence of QS in filamentous fungi. Lipophilic molecules, including lactone-based molecules and the oxygenated poly-unsaturated fatty acids, oxylipins, are the major signalling molecules reported in filamentous fungi. This study correlates the cell-densities of filamentous fungi to the regulation of their different physiological responses. Two fungal species have been investigated. The first is Penicillium sclerotiorum. It was found that addition of ethyl acetate extracts from high cell densities of P. sclerotiorum culture increases sporulation delays the onset of hyphal branching and enhances the production of the secondary metabolite, sclerotiorin in shaken flasks as well as stirred tank bioreactors (STR). GC-MS analysis of the high cell-density extracts revealed several molecules including the oxylipin ricinoleic acid that might be involved in the regulation of the P. sclerotiorum physiological responses via QS. The second species studied was Aspergillus terreus. Here, the role of oxylipins as signalling molecules was investigated. It was found that the supplementation of linoleic acid, as an oxylipin precursor, enhances the production of the secondary metabolite lovastatin in shaken flasks and STRs. Studies using linoleic acid were extended, to investigate its effect on the cytosolic proteome profile of A. terreus. Re…
author: Amache, R.
date published: 2014
date modified: 2026-07-24T06:02:22Z
provider: University of Westminster
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Westminster

PropertyValue
property ID: DOI
value: 10.34737/8y9x2