Purification and characterization of a fungal laccase expressed in Kluyveromyces lactis suitable for baking

MOLINA, MELISA A.; CAZZANIGA, AMANDA; MILDE, LAURA B.; SGROPPO, SONIA C.; ZAPATA, PEDRO D.; FONSECA, MARIA I.

JOURNAL OF FOOD SCIENCE

WILEY-BLACKWELL PUBLISHING, INC

Año: 2023

0022-1147

Laccase enzyme can replace chemical additives to improve tex-ture properties and the volume of bread. Laccase encoding gene fromPhlebiabrevispora, a native fungus from Misiones, Argentina, was expressed in the gen-erally recognized as safe yeastKluyveromyces lactis. To improve laccase activity,medium conditions were optimized. The use of iron sulfate at a concentration of1 mM led to optimum laccase activity (1289 U⋅L−1) on the fourth day of incuba-tion.SDS-PAGEanalysisrevealedthatthemolecularmassofpurifiedlaccasewasabout 180 kDa. Optimum pH for the enzyme was 4 and optimum temperaturewas 40◦C. Laccase exhibited high stability at low pH and high temperature. Theapplication of recombinant laccase to bread decreased hardness, gumminess,and chewiness and increased bread volume. Based on these results, recombinantlaccase fromP. brevisporawith improved yield is a good option for applicationas an improver of the physicochemical quality of bread at the industrial level.Besides,itwillallowustoadvancetowardourgoalofdevelopinghealthyalterna-tives for the bakery industry. No previous work has been reported concerning theheterologous expression of the laccase gene native to the province of Misiones,Argentina, with an aim for application in baking