A New Subtilase-Like Protease Deriving from Fusarium equiseti with High Potential for Industrial Applications

Abstract

A gene encoding a novel extracellular subtilisin-like protease was cloned from the ascomycete Fusarium equiseti and expressed in Trichoderma reesei. The F. equiseti protease (Fe protease) showed excellent performance in stain removal and good compatibility with several commercial laundry detergent formulations, suggesting that it has high potential for use in various industrial applications. The recombinant enzyme was purified and characterized. The temperature optimum of the Fe protease was 60 °C and it showed high activity in the pH range of 6-10, with a sharp decline in activity at pH above 10. The amino acid specificity of the Fe protease was studied using casein, cytochrome c, and ubiquitin as substrates. The Fe protease had broad substrate specificity: almost all amino acid residues were accepted at position P1, even though it showed some preference for cleavage at the C-terminal side of asparagine and histidine residues. The S4 subsite of Fe protease favors aspartic acid and threonine. The other well-characterized proteases from filamentous fungi, Proteinase K from Engyodontium album, Thermomycolin from Malbranchea sulfurea, and alkaline subtilisins from Bacillus species prefer hydrophobic amino acids in both the S1 and S4 subsites. Due to its different specificity compared to the members of the S8 family of clan SB of proteases, we consider that the Fe protease is a new protease. It does not belong to any previously defined IUBMB groups of proteases.

Toxic, but beneficial compounds from endophytic fungi of Carica papaya

“…F. equiseti is also employed as a plant growth promoting fungus (82,83). Also, an F. equiseti-dreived protease showed excellent stain removal property and was compatible with several commercial laundry detergent formulations (85).…”

Potential absorption of mercury-contaminated substrate by Trichoderma sp isolated from Brazil Nuts and Amazon Soil

“…With respect to mercury at 200 mg/L there was total inhibition of fungus growth for TCH 1 and 2 whereas for TCH 3, 4 and 5 the growth started only after 60 hours and with noticeable effect of mercury retarding both growth and sporulation. Also, Juntunen et al (2015) showed that at optimum temperature, Fe protease showed high activity in the pH range of 6-10, with a sharp decline in activity at pH above 9.0.…”

Specificity of peptidases secreted by filamentous fungi

“… Unprimed Subsites Primed Subsites Microorganism Classification S 5 S 4 S 3 S 2 S 1 S ’ 1 S ’ 2 S ’ 3 S ’ 4 S ’ 5 Substrate Ref. Fusarium equiseti Subtilase-like ND Asn Gly Thr His Tyr Gly Lys Gly ND Hydrolysis profile of the β-casein, cytochrome c and ubiquitin [ 18 ] Aspergillus fumigatus Sedolisin (SedA) ND ND ND ND ND ND ND ND ND ND Resorufin-labeled casein [ 19 ] Talaromyces emersonii Prolyl aminopeptidases ND ND ND ND Pro ND ND ND ND …”