New screening technique paves the way for protein drugs from bacteria

(Press-News.org) A cheaper, more efficient technique for developing complex protein drugs from bacteria has been developed at the University of Sheffield.

Using the bacterium E. coli, researchers from the University's Faculty of Engineering showed it was possible to vastly increase the efficiency of the cells producing specifically modified proteins, as well as improve its performance and stability. The modification is present in over two-thirds of human therapeutic drugs on the market and involves the addition of specific sugar groups to the protein backbone, a process termed glycosylation.

Drugs based on proteins are increasingly important in modern medicine to tackle health problems including diabetes, cancer and arthritis.

Although simple proteins are traditionally made in microbial cells, these types of complex drugs are made using animal cells because they can make human-type glycosylations that will control its efficacy and stability in the body, and avoid immunogenic reactions in patients.

Using bacteria to make proteins for use as medicines could be a more cost effective alternative, since using animal cells is expensive. However, the efficiency of glycoprotein production in bacterial cells is still very poor, with yields often several thousand times lower than in animal cells.

Now, researchers in the Department of Chemical and Biological Engineering at the University of Sheffield, with collaboration from the University of Colorado, are using a technique called inverse metabolic engineering, that allows them to screen cells to identify strains that are likely to be the most efficient glycoprotein producers. Using this method, the team were able to produce seven times as much of the protein in laboratory tests.

The team then used mass spectrometry to characterise and accurately quantify the proteins being produced by the bacteria. This allowed them to pinpoint modifications that will enable them, ultimately, to improve the performance of the drug.

Professor Phil Wright, who led the research, said: "We believe that this technique will pave the way for pharmacologists to get the same protein yield from bacteria cells as they could from animal cells and also enable them to produce drugs from bacteria that have vastly improved focus and accuracy."

The team also tested the technique on antibody fragments with positive results, showing that their approach could work in different proteins.

### The study, published in the journal Biotechnology and Bioengineering, was funded by the Biotechnology and Biological Sciences Research Council (BBSRC). A further BBSRC BRIC grant will enable the team to continue to improve their results and explore other applications for the technology.

Notes to editors: 1. "Inverse Metabolic Engineering to Improve Escherichia coli as an N-Glycosylation Host", by Jagroop Pandhal, Lauren B. A. Woodruff, Stephen Jaffe, Pratik Desai, Saw Y. Ow, Josselin Noirel, Ryan T. Gill, Phillip C. Wright, is published in Biotechnology and Bioengineering. 2. The Faculty of Engineering at the University of Sheffield - the 2011 Times Higher Education's University of the Year - is one of the largest in the UK. Its seven departments include over 4,000 students and 900 staff and have research-related income worth more than £50M per annum from government, industry and charity sources. The 2008 Research Assessment Exercise (RAE) confirmed that two thirds of the research carried out was either Internationally Excellent or Internationally Leading. The Faculty of Engineering has a long tradition of working with industry including Rolls-Royce, Network Rail and Siemens. Its industrial successes are exemplified by the award-winning Advanced Manufacturing Research Centre (AMRC) and the new £25 million Nuclear Advanced Manufacturing Research Centre (NAMRC). The Faculty of Engineering is set to ensure students continue to benefit from world-class labs and teaching space through the provision of the University's new Engineering Graduate School. This brand new building, which will become the centre of the faculty´s postgraduate research and postgraduate teaching activities, will be sited on the corner of Broad Lane and Newcastle Street. It will form the first stage in a 15 year plan to improve and extend the existing estate in a bid to provide students with the best possible facilities while improving their student experience. To find out more about the Faculty of Engineering, visit: http://www.shef.ac.uk/faculty/engineering/ 3. About BBSRC The Biotechnology and Biological Sciences Research Council (BBSRC) invests in world-class bioscience research and training on behalf of the UK public. Our aim is to further scientific knowledge, to promote economic growth, wealth and job creation and to improve quality of life in the UK and beyond. Funded by Government, and with an annual budget of around £500M (2012-2013), we support research and training in universities and strategically funded institutes. BBSRC research and the people we fund are helping society to meet major challenges, including food security, green energy and healthier, longer lives. Our investments underpin important UK economic sectors, such as farming, food, industrial biotechnology and pharmaceuticals. For more information about BBSRC, our science and our impact see: http://www.bbsrc.ac.uk For more information about BBSRC strategically funded institutes see: http://www.bbsrc.ac.uk/institutes