Exoglucanase 1 (Cellobiohydrolase I) (Cel7A)

Cel7A, also known as Exoglucanase 1 or Cellobiohydrolase I (CBH1), is a major cellulolytic enzyme primarily secreted by filamentous fungi such as Trichoderma reesei [1]. It belongs to the Glycosyl Hydrolase Family 7 (GH7) and plays a pivotal role in the natural carbon cycle by breaking down crystalline cellulose into cellobiose [2]. The enzyme's structure is modular, featuring a catalytic domain with a tunnel-shaped active site and a cellulose-binding module (CBM) that anchors the enzyme to its insoluble substrate [1, 3]. Cel7A is the workhorse of the industrial enzyme industry, being the most abundant component in commercial cellulase preparations used for the production of second-generation biofuels from plant biomass [4]. Although it is not a target for human clinical therapeutics, it is a significant target for protein engineering aimed at increasing its thermostability and catalytic efficiency to reduce the cost of renewable energy production [2, 4].

Other names

CBH1Cellobiohydrolase I1,4-beta-cellobiohydrolaseGlycosyl hydrolase family 7 memberExocellulase 1

No therapeutic drugs currently target this enzyme; however, its catalytic mechanism involves the processive hydrolysis of crystalline cellulose from the reducing end to release cellobiose [2, 3].