Tandem Ubiquitin Binding Entities (TUBEs) consist of repeated ubiquitin binding domains engineered to increase affinity and specificity. TUBEs are used for pull-downs from lysates, Western blots, and fluorescence applications. Currently, our product line contains K63-, K48-, M1- (linear) and non-selective TUBEs. We are expanding this line of products to include a TUBE reagent selective for each polyubiquitin chain linkage.
This is one of the most fundamental and common questions that customers ask us. To answer the question, we put together a straightforward kit that provides several advantages over traditional methods. In summary, you pull down ubiquitylated targets with TUBEs, elute the targets, treat half of the sample with the general debubiquitylase USP2core, and perform a Western blot for your protein of interest. USP2core serves as an internal control to demonstrate that higher molecular weight species were a result of ubiquitylation. Additionally, some target antibodies do not sensitively recognize the ubiquitylated target, and USP2core circumvents this issue. We are expanding this idea to chain-specific applications and you can purchase a K48 or K63 selective version to investigate chain linkage. UbiTest Alpha is the classic USP2core version, UbiTest Scout adds one linkage-specific DUB, and UbiTest Pack includes all currently available enzymes – USP2core + AMSHcore (K63) + OTUB1 (K48).
The UbiQuant S kit allows researchers to quantitatively measure ubiquitylation of a specific substrate from cell lysates. (The original UbiQuant measures total ubiquitylation.) The first version of UbiQuant S is an ELISA format. We are also developing a high throughput version utilizing AlphaLISA technology from Perkin Elmer. Additionally, we are working on versions that detect specific polyubiquitin linkages based on our TUBE technology.
Rapid advances in genomics and proteomics have led to the discovery of many novel gene and protein sequences. However, production of biologically active proteins remains a major bottleneck to the study of the structure and function of proteins, the generation of therapeutic proteins, and the identification of novel drug targets. LifeSensors’s SUMOpro™ fusion technology addresses this bottleneck by enhancing the expression and solubility of proteins in E. coli and facilitating rapid purification of biologically active proteins.
The use of the SUMOpro system, however, is restricted to E.coli. The LifeSensors team has engineered SUMOstar – novel SUMO tags designed specifically to enhance expression and purification of recombinant proteins from eukaryotic cells. LifeSensors’s proprietary family of SUMO and SUMOstar proteases specifically cleave SUMO and SUMOstar tags to produce native protein with a desired N-terminus, which is very important in the production of therapeutic proteins. Furthermore, LifeSensors is developing various affinity matrices, antibodies, and novel tools for the purification of SUMO-tagged fusion proteins. For an abbreviated list of publications that used the SUMO tag to purify proteins click here.
The development of economically feasible protein production processes is a major hurdle in taking vaccines, peptides, and therapeutic proteins from discovery and preclinical development to the market. LifeSensors has worked with a number of pharmaceutical and biotechnology companies using its SUMOpro and SUMOstar systems to express and purify proteins for therapeutic use, as well as for structure and functional studies. For high value proteins that fail to express in other systems, the LifeSensors protein production technologies are especially useful. LifeSensors performs contract expression and purification services based on FTEs and the value of the protein. The superiority of the LifeSensors expression system has been demonstrated by:
Protein ubiquitylation is a dynamic process involving a careful balance between the activity of ubiquitin ligases and their antagonists – the ubiquitin-specific proteases or deubiquitylating enzymes (DUBs), which mediate the removal and processing of ubiquitin. Similar to the ubiquitin pathway, pathways involving ubiquitin-like proteins such as SUMO, ISG15 and NEDD8 play critical roles in many cellular functions. Enzymes that remove SUMO (De-SUMOylases), ISG15 (De-ISGinylases), and NEDD8 (De-NEDDylases) are important targets as biomarkers of disease and targets for drug discovery. There are approximately 100 DUBs encoded in the human genome; many of them play critical roles in cellular physiology. LifeSensors is currently marketing numerous DUBs and their antibodies, and its ultimate goal is to market all of them. Please view our DUBs.