Carboxyl Methyltransferases: Natural Functions and Potential Applications in Industrial Biotechnology

Abstract

The use of methyltransferases (MTs) in industrial biotechnology to replace toxic alkylating agents is of increasing interest. Carboxyl MTs (CMTs) are a subgroup of MTs that methylate the hydroxyl oxygen of carboxylic acids. Research initially focussed on their natural functions in protein regulation and production of volatile methyl esters in plants. In this review we highlight this potentially valuable group of enzymes that show promise for formation of a wide range of structurally diverse methyl esters from the parent acids under aqueous conditions. CMTs have been used to generate intermediates for biofuels, bioplastics and pharmaceuticals. These biocatalysts could also be integrated into cascades with other enzymes such as acyltransferases that function under aqueous conditions. Recent approaches for regenerating the required cofactor S‐adenosylmethionine (SAM) are discussed including in vitro recycling, improvement in in vivo production and the use of more stable analogues. Advances in these areas will further improve the potential to use carboxyl MTs in industrial biotechnology.

Characterisation and heterologous biosynthesis of burnettiene A, a new polyene-decalin polyketide from Aspergillus burnettii

“…39 Additionally, carboxyl methyltransferases such as BueF are of biotechnological interest. 40 Heterologous expression of bue genes in the chassis A. nidulans proved a more favourable strategy for the production and isolation of 1 than in the native host, obtaining a ~45-fold increase in the yield of 1 per kg of substrate compared to A. burnettii. 3 Interestingly, we also observed that the strains of A. nidulans harbouring AMA1-based episomal vectors, which require auxotrophy selection for maintenance, can sustain production in grain substrates such as jasmine rice with yields as high as 468 mg/kg in the case of 2.…”

Characterisation and heterologous biosynthesis of burnettiene A, a new polyene-decalin polyketide from Aspergillus burnettii

“…37 Additionally, carboxyl methyltransferases such as BueF are of biotechnological interest. 38 Heterologous expression of bue genes in the chassis A. nidulans proved a more favourable strategy for the production and isolation of 1 than in the native host, obtaining a ~45-fold increase in the yield of 1 per kg of substrate compared to A. burnettii. 4 Interestingly, we also observed that the strains of A. nidulans harbouring AMA1-based episomal vectors, which require auxotrophy selection for maintenance, can sustain production in grain substrates such as jasmine rice with yields as high as 468 mg/kg in the case of 2.…”

Characterisation and heterologous biosynthesis of burnettiene A, a new polyene-decalin polyketide from Aspergillus burnettii

“…37 Additionally, carboxyl methyltransferases such as BueF are of biotechnological interest. 38 Heterologous expression of bue genes in the chassis A. nidulans proved a more favourable strategy for the production and isolation of 1 than in the native host, obtaining a ~45-fold increase in the yield of 1 per kg of substrate compared to A. burnettii. 4 Interestingly, we also observed that the strains of A. nidulans harbouring AMA1-based episomal vectors, which require auxotrophy selection for maintenance, can sustain production in grain substrates such as jasmine rice with yields as high as 468 mg/kg in the case of 2.…”