TY - JOUR

T1 - Moderately thermostable GH1 β-glucosidases from hyperacidophilic archaeon Cuniculiplasma divulgatum S5

AU - Khusnutdinova, Anna

AU - Hai, Tran

AU - Devlekar, Saloni

AU - Distaso, Marco

AU - Kublanov, Ilya V.

AU - Skarina, Tatiana

AU - Stogios, Peter

AU - Savchenko, Alexei

AU - Ferrer, Manuel

AU - Golyshina, Olga

AU - Yakunin, Alexander

AU - Golyshin, Peter

PY - 2024/8/10

Y1 - 2024/8/10

N2 - Family GH1 glycosyl hydrolases are ubiquitous in prokaryotes and eukaryotes and are utilised in numerous industrial applications, including bioconversion of lignocelluloses. In this study, hyperacidophilic archaeon Cuniculiplasma divulgatum (S5T=JCM 30642T) was explored as a source of novel carbohydrate-active enzymes. The genome of C. divulgatum encodes three GH1 enzyme candidates, from which CIB12 and CIB13 were heterologously expressed and characterised. Phylogenetic analysis of CIB12 and CIB13 clustered them with β-glucosidases from genuinely thermophilic archaea including Thermoplasma acidophilum, Picrophilus torridus, Sulfolobus solfataricus, Pyrococcus furiosus and Thermococcus kodakarensis. Purified enzymes showed maximal activities at pH 4.5–6.0 (CIB12) and 4.5–5.5 (CIB13) with optimal temperatures at 50 °C, suggesting a high-temperature origin of Cuniculiplasma spp. ancestors. Crystal structures of both enzymes revealed a classical (α/β)8 TIM barrel fold with the active site located inside the barrel close to the C-termini of β-strands including the catalytic residues Glu204 and Glu388 (CIB12), and Glu204 and Glu385 (CIB13). Both enzymes preferred cellobiose over lactose as substrates and were classified as cellobiohydrolases. Cellobiose addition increased the biomass yield of Cuniculiplasma cultures growing on peptides by 50%, suggesting that the cellobiohydrolases expand the carbon substrate range and hence environmental fitness of Cuniculiplasma.

AB - Family GH1 glycosyl hydrolases are ubiquitous in prokaryotes and eukaryotes and are utilised in numerous industrial applications, including bioconversion of lignocelluloses. In this study, hyperacidophilic archaeon Cuniculiplasma divulgatum (S5T=JCM 30642T) was explored as a source of novel carbohydrate-active enzymes. The genome of C. divulgatum encodes three GH1 enzyme candidates, from which CIB12 and CIB13 were heterologously expressed and characterised. Phylogenetic analysis of CIB12 and CIB13 clustered them with β-glucosidases from genuinely thermophilic archaea including Thermoplasma acidophilum, Picrophilus torridus, Sulfolobus solfataricus, Pyrococcus furiosus and Thermococcus kodakarensis. Purified enzymes showed maximal activities at pH 4.5–6.0 (CIB12) and 4.5–5.5 (CIB13) with optimal temperatures at 50 °C, suggesting a high-temperature origin of Cuniculiplasma spp. ancestors. Crystal structures of both enzymes revealed a classical (α/β)8 TIM barrel fold with the active site located inside the barrel close to the C-termini of β-strands including the catalytic residues Glu204 and Glu388 (CIB12), and Glu204 and Glu385 (CIB13). Both enzymes preferred cellobiose over lactose as substrates and were classified as cellobiohydrolases. Cellobiose addition increased the biomass yield of Cuniculiplasma cultures growing on peptides by 50%, suggesting that the cellobiohydrolases expand the carbon substrate range and hence environmental fitness of Cuniculiplasma.

U2 - 10.1093/femsec/fiae114

DO - 10.1093/femsec/fiae114

M3 - Article

JO - Fems Microbiology Ecology

JF - Fems Microbiology Ecology

SN - 0168-6496

ER -