1 Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Graz, Austria; Austrian Centre of Industrial Biotechnology (acib), Graz, Austria. Electronic address: bernd.nidetzky@tugraz.at.
2 School of Chemical and Biological Engineering and BIO-MAX Institute, Seoul National University, Seoul, South Korea. Electronic address: byungkim@snu.ac.kr.