Proteios History- What does Car9 mean, anyway?
Proteios Technology CEO Bob Snyder, Ph.D.
Proteios had its origin back in 2015. I was working with researchers at the University of Washington to identify if their technology had commercial potential and to assist them in applying for an initial grant from the University to perform the analysis. In one project, I worked with Prof. Francois Baneyx in the Bioengineering Department. His lab had identified a dodecapeptide that binds to silica with high affinity and had the potential to form the basis of a new affinity tag for the purification of recombinant proteins. The dodecapeptide was identified by Brandon Coyle, a graduate student in Prof. Baneyx’s lab at the time. Brandon recalls the process as follows:
“The Car9 tag has a long history. Originally discovered using an E. coli random display library, we were looking for carbon binding proteins. This technique relies on sheer numbers to find something out of a random set of protein sequences. It’s truly a one-in-a-million chance. The name stems from the fact that it’s the 9th carbon binder we sequenced (e.g., Car9 for short). As with many scientific discoveries, the conversion to a silica binding purification tag came out of failure. We wanted to analyze the ability of the carbon tag to bind to different carbon surfaces so we appended it to the end of a green fluorescent protein so we could see the binding by fluorescence. This worked wonderfully for a few other carbon binding sequences but for Car9, we couldn’t see any protein on the carbon surfaces. In fact, we couldn’t find the fluorescent protein at all in our field of view of the microscope. After many frustrating hours, we stumbled upon the protein, and it wasn’t on the carbon beads at all, but rather the surface of our microscope slide. The microscope slides were made from silica, and for fans of the periodic table, silica sits just below carbon. As a result, it shares many of the same surface chemistries - so not only did we have a carbon binder but a silica binder as well. That discovery led to many follow-on ideas, cost-effective protein purification using silica matrices, stamping protein patterns on glass, oriented attachment to specific carbon chemistries to name a few.”
Prof. Baneyx and I decided to spin out the technology in order to share it with other researchers – and Proteios was born. The University received a patent for the Car9 affinity tag and Proteios obtained a worldwide, exclusive license to commercialize the technology. Proteios received SBIR Phase I & II grants from the National Science Foundation (NSF) to create a series of recombinant protein purification kits based on the Car9 affinity tag.
That brings us to today – with the commercial launch of five protein purification kits based on the Car9 affinity tag. Thanks to the many scientists at Proteios and to funding by NSF, we are finally able to deliver on the original promise of sharing this technology with the research community.