Systems biology and biological systems diversity for the engineering of microbial cell factories

Metabolic engineering was originally conceived as a systems approach to optimise biotechnologically desired traits of microbes and higher cells [1]. Microbial Cell Factories has published several review and research articles on this field over the past recent years [2-8]. Although clear breakthroughs have been achieved in the past, progress in metabolic engineering has been largely limited to individual pathways or relatively simple networks. Engineering of complex metabolic networks has been hampered by the insufficient biological information and global analytical tools.