Production of recombinant cutinases and their potential applications in polymer hydrolysis: The current status

Cutinases are enzymes that degrade cutin, a component of plant cuticles. Although these enzymes play biological roles in plant pathogenic microorganisms, researchers suggested their use in various applications, particularly in plastic degradation. For that, heterologous expression systems are primarily employed for their production. Various types of expression systems for recombinant cutinase production are reported in the literature, in which Escherichia coli and Pichia pastoris stand out as the most common and highest-yielding systems, but the production is also feasible in filamentous fungi. Nonetheless, it has been established that the application of wild-type enzymes in polymer hydrolysis is inefficient. So, numerous studies have pivoted to genetic engineering strategies to overcome the inherent limitations of enzymes, mostly thermostability and enzymatic activity. Current reviews on cutinases focus on their applications in plastic degradation, their functional characteristics, and their degradation mechanisms for different substrates. Our group has performed a different approach with an extensive review of recombinant cutinase production and provides an overview of the employed expression systems, the fundamental traits of each host organism, the primary optimizations implemented regarding protein engineering strategies, and offers an update on the prospective applications of cutinases. Hence, this review consolidates the most current knowledge on recombinant cutinases.