An extracellular carboxylesterase from the basidiomycete Pleurotus sapidus hydrolyses xanthophyll esters

Abstract

An extracellular enzyme capable of efficient hydrolysis of xanthophyll esters was purified from culture supernatants of the basidiomycete Pleurotus sapidus. Under native conditions, the enzyme exhibited a molecular mass of 430 kDa, and SDS-PAGE data suggested a composition of eight identical subunits. Biochemical characterisation of the purified protein showed an isoelectric point of 4.5, and ideal hydrolysis conditions were observed at pH 5.8 and 40 degrees C. Partial amino acid sequences were derived from N-terminal Edman degradation and from mass spectrometric ab initio sequencing of internal peptides. An 1861-bp cDNA containing an open reading frame of 1641 bp was cloned from a cDNA library that showed ca. 40% homology to Candida rugosa lipases. The P. sapidus carboxylesterase represents the first enzyme of the lipase/esterase family from a basidiomycetous fungus that has been characterised at the molecular level.

Genome mining of fungal lipid-degrading enzymes for industrial applications

“…The majority of the predicted proteins in the carboxylesterase family were extracellular proteins (23 protein sequences; 57.5 % of total COesterase) and cytoplasmic proteins (13 protein sequences; 32.5 % of total COesterase). These results are consistent with previous studies demonstrating that both extracellular and intracellular activities of carboxylesterase enzymes have been detected in several micro-organisms (Donaghy & McKay, 1992;Molinari et al, 2000;Dröge et al, 2005;Zorn et al, 2005). The N-terminal signal peptide, which is anchored to the cell wall, was detected in the extracellular carboxylesterases similar to other extracellular lipase proteins, such as extracellular triacylglycerol lipase (lipase class3) and phopholipase (PLA2_B) families.…”

Effect of mycelial morphology on ergothioneine production during liquid fermentation of Lentinula edodes

“…Previous studies on image analyses of Paecilomyces japonicus have reported that mycelial morphology markedly affects mycelial growth and biopolymer production (Sinha et al 2001). However, extensive studies on the relationship between morphological parameters and productivity of fermentation products are still scarce (Zorn et al 2005;Alvim et al 2009;Rühl 2009). …”

Volatiles from submerged and surface‐cultured beefsteak fungus, Fistulina hepatica

“…Best investigated are surface cultures which were shown to produce reactive oxygen species 34 and numerous enzymes catalysing the efficient degradation of lignin 33 and other robust substrates (Figure 1). 35 Some mechanistic insight has been gained into these processes, and some immediate chemical inducers, such as 2,5-dimethoxybenzyl alcohol (for laccases) 36 and iron (for general mRNA regulation and iron acquisition), 37 have been identified. Little is known, however, about the role of water activity 38 and light 39 on cellular differentiation.…”