Our client needed a biotinylated version of a highly disordered protein for their high-throughput screening assay. Previous work with the protein of interest had demonstrated issues with protein stability and loss of protein during concentration using centrifugal concentrators; we were therefore concerned about further [...]
Sherlock Holmes and the Case of the Missing Cysteines.
Peak Proteins2024-04-22T15:41:36+00:00We had been asked by a client to express and purify a protein:Fab complex to support a Cryo-EM project. This was just to be a reproduction of a crystal structure that had been reported in the literature and so on the face of it [...]
Producing Homotrimeric Proteins
Helen Barclay2022-04-26T08:22:53+00:00Many proteins exist and function as multimers in their native state. However, the mechanism by which they achieve this can prove to be an issue when trying to express and purify the protein recombinantly. Two recent projects we have been involved with, required solutions to [...]
Identification of Novel Post Translational Modifications of a Recombinantly Expressed Peptide
Peak Proteins2023-06-19T15:45:54+00:00A client had requested to obtain a small peptide that was <10kDa, normally processed by cleavage of a larger precursor protein, to be supplied as an untagged recombinant protein. At Peak Proteins, we have experience working with expressing and purifying this type of peptide. [...]
The Importance of Protein Construct Design
Peak Proteins2023-09-21T14:29:18+00:00Early on in any recombinant protein expression and purification project, there are many factors that we at Peak Proteins consider as part of the protein construct design process. It cannot be understated the importance of committing time and effort to this stage, as the [...]
Optimising Endoglycosidase H Treatment of Proteins – All Thanks to Cauliflowers!
Peak Proteins2024-10-21T10:49:33+00:00In a previous case study, we have described the benefits of using the HEK293 suspension cell system in combination with the mannosidase inhibitor, kifunensine, and endoglycosidase H (EndoH) treatment to successfully crystallise complex proteins by removing bulky, N-linked oligosaccharides. Increasingly, we are relying on [...]
Using EDTA as a Strategy to Reduce Protein Aggregation
Peak Proteins2022-04-21T10:52:56+00:00A client requested the large-scale production of a protein that had previously been optimised for purification during feasibility studies. This protein had proven tricky to purify during the feasibility stage and two attempts had been taken to establish a suitable purification strategy. High protein [...]
Method Optimisation and Protein Production for a High Throughput Screen
Peak Proteins2022-04-21T10:53:19+00:00A client requested assistance providing protein to enable a high throughput screen (HTS). This was for an emerging target that was implicated in the development of neurodegenerative diseases, strokes, and epileptic seizures. Their yields of purified protein from E.coli were around 1mg/L, with initial [...]
Using Peptide Mapping to Reveal Glycosylated and Non-Glycosylated Protein Forms
Peak Proteins2022-05-18T08:15:21+00:00A client had requested us to express and purify a protein for assay studies. Six 6His tagged constructs were designed to increase the chances of obtaining a suitable form of protein that could be tested in assays. After E.coli expression and nickel sepharose affinity [...]
Expression, Purification and Biotinylation of a Heterotrimeric Protein Complex
Peak Proteins2023-03-15T16:56:54+00:00A client requested the production of biotinylated and non-biotinylated heterotrimeric complex to support assay screening and biophysics. The protein complex plays a role in tumour suppression, and thus can be used to identify novel targeted therapies. Proteins A and B were cloned into [...]
