Biology Research

Prokaryotic expression system (E. coli expression system) is a classical system developed earlier and widely used in gene expression technology. In recent decades, the E. coli expression system has been continuously developed and improved, and has been widely adopted by scientific research and industrial users for expressing various recombinant proteins. Compared with other expression systems, it is characterized by high expression levels of target genes, short culture periods, strong pollution resistance, and low cost.

PROTACs (proteolysis-targeting chimeras) are bifunctional small molecules that can target otherwise undruggable proteins for degradation, thereby reducing their biological activity in a cell. They can be understood as dumbbell-shaped chimeras, with one end targeting the protein to be degraded and the other recruiting protein degradation systems such as E3 ubiquitin ligase, connected by a suitable linker. This forms a ternary chimera featuring the target protein, PROTAC, and E3 ubiquitin ligase, ensuring close proximity between the target protein and E3 ligase. Consequently, the target protein can be ubiquitinated, recognized, and further degraded by the proteasome. In theory, this new mechanism can target all drug target proteins, especially those previously considered undruggable, thereby expanding the field of drug research and promising prospects for new drug R&D. PROTAC technology is novel and offers many advantages compared to traditional micromolecule drugs, antibody drugs, and RNAi. It is considered one of the most popular new modalities in drug discovery, and Medicilon has extensive experience in PROTAC development.

Medicilon's Biology Department has extensive research experience in preparing recombinant kinases. We utilize various expression systems, including insect cell expression systems, HEK293 cell expression systems, and E. coli expression systems. To support the selection, discovery, and development of kinase-targeting drugs, we offer a range of kinase research solutions from method development for detection, high-throughput screening, to selective analysis. We actively engage with our clients, understand their specific needs, and provide comprehensive experimental technical solutions.

Monoclonal antibodies include an antigen-binding fragment (Fab) and a fragment crystallizable region (Fc). The Fab can bind to a tumor-associated antigen, while the Fc plays an important role in metabolic pathways, as well as in IgG-driven cellular functions.The molecular sequence and subtype of antibodies will affect the effector functions. Such effector functions include the antibody dependent cellular cytotoxicity (ADCC) triggered by Fc binding to the FcγRIII receptor (CD16A) of NK. The Fc can also bind with serum complement molecules (C1q) to form a membrane attack complex (MAC) that triggers complement-dependent cytotoxicity (CDC). When Fc binds with macrophage receptors—namely FcγRIII (CD16A), FcγRII (CD32A) and FcγRI (CD64)—antibody-dependent cellular phagocytosis (ADCP) is triggered.