Applied Microbiology and Biotechnology | VOL. 106

Modifying a bacterial tyrosinase zymogen for use in protease activity assays

Publication Date Nov 21, 2022


Current clinical laboratory assays are not sufficient for determining the activity of many specific human proteases yet. In this study, we developed a general approach that enables the determination of activities of caspase-3 based on the proteolytic activation of the engineered zymogen of the recombinant tyrosinase from Verrucomicrobium spinosum (Vs-tyrosinase) by detecting the diphenolase activity in an increase in absorbance at 475nm. Here, we designed three different zymogen constructs of Vs-tyrosinase, including RSL-pre-pro-TYR, Pre-pro-TYR, and Pro-TYR. The active domain was fused to the reactive site loop (RSL) of α1-proteinase inhibitor and/or its own signal peptide (pre) and/or its own C-terminal domain (pro) via a linker containing a specific caspase-3 cleavage site. Further studies revealed that both RSL peptide and TAT signal peptide were able to inhibit tyrosinase diphenolase activity, in which RSL-pre-pro-TYR had the lowest background signals. Therefore, a specific protease activity such as caspase-3 could be detected when a suitable zymogen was established. Our results could provide a new way to directly detect the activities of key human proteases, for instance, to monitor the efficacy and safety of tumor therapy by determining the activity of apoptosis-related caspase-3 in patients. KEY POINTS: • RSL inhibited the activity of Verrucomicrobium spinosum tyrosinase. • N-pre and C-terminal domain exerted stronger dual inhibition on the Vs-tyrosinase. • The activity of caspase-3 could be measured by the zymogen a...


Activity Of Caspase-3 Reactive Site Loop TAT Signal Peptide Caspase-3 In Patients Protease Activity Assays Verrucomicrobium Spinosum Specific Protease Activity Diphenolase Activity Human Proteases Current Clinical Assays

Round-ups are the summaries of handpicked papers around trending topics published every week. These would enable you to scan through a collection of papers and decide if the paper is relevant to you before actually investing time into reading it.

Climate change Research Articles published between Jan 23, 2023 to Jan 29, 2023

R DiscoveryJan 30, 2023
R DiscoveryArticles Included:  3

Climate change adaptation has shifted from a single-dimension to an integrative approach that aligns with vulnerability and resilience concepts. Adapt...

Read More

Coronavirus Pandemic

You can also read COVID related content on R COVID-19

R ProductsCOVID-19


Creating the world’s largest AI-driven & human-curated collection of research, news, expert recommendations and educational resources on COVID-19

COVID-19 Dashboard

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on “as is” basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The Copyright Law.