our science
our science
Sense Proteomic's arrays comprise sets of human proteins immobilised onto a solid support. For functional studies, it is essential that arrayed proteins are correctly folded and active. This is achieved by using a proprietary tag - biotin carboxyl carrier protein (BCCP) - which is biotinylated only when correctly folded. Biotinylation therefore acts as an indicator of protein folding. By arraying proteins directly onto a streptavidin surface, only biotinylated (and therefore correctly folded) proteins are attached to the slide surface. This screen for protein folding and affinity purification directly on the slide surface is unique and produces highly reproducible protein arrays, a requirement for producing meaningful quantitative data.
Arrayed proteins are:
To manufacture the arrays Sense Proteomic uses a protein-resistant surface coated with streptavidin on precision glass microarray slides. The streptavidin provides a specific and high affinity capture system for the biotinylated tagged proteins while the protein-resistant surface provides a background with exceptionally low non-specific binding.
All proteins are expressed in insect cells using a baculovirus expression system. All proteins are sequence verified and correspond to publicly available reference sequences. The cartoon below depicts the discrimination afforded by the unique BCCP tagging system. The BCCP tag (blue) is folded correctly only when the protein (brown) is folded correctly. Correct folding of the BCCP tag is a pre-requisite for biotinylation of the tag by an enzyme in the insect cells. This ensures that only correctly folded proteins are immobilised to the slide.
Cell lysates containing the desired tagged proteins are spotted directly onto the slides. When the tagged proteins are incubated, only the biotinylated BCCP tagged proteins bind to the streptavidin-coated surface. Non-biotinylated proteins (e.g. endogenous insect cell proteins) are not bound and are subsequently washed away.
Washing removes all other cellular material from the surface of the array. Because the immobilisation is via the tag, the resulting arrays contain only homogenously oriented proteins which are projected into the aqueous phase. This reduces non-specific adsorption to the slide surface and allows greater access of assay reagents to the proteins.
Sense Proteomic arrays can be used to study:
