“…The natural substrate spectrum of C. glutamicum further includes sugars like ribose or maltose, alcohols like ethanol or myo ‐inositol and organic acids like acetate, citrate, lactate, propionate and pyruvate and amino acids like l ‐glutamate (Kramer et al ., ; Dominguez et al ., ; Kiefer et al ., ; Gerstmeir et al ., ; Eikmanns, ; Moon et al ., ; Polen et al ., ; Stansen et al ., ; Krings et al ., ; Frunzke et al ., ; Kato et al ., ; Neuner and Heinzle, ). Within the flexible feedstock concept, the substrate spectrum of C. glutamicum has been extended by metabolic engineering to allow access to starch, cellobiose, lactose, galactose and glycerol as well as succinate, fumarate and malate as carbon sources (Brabetz et al ., ; Cadenas et al ., ; Kotrba et al ., ; Barrett et al ., ; Seibold et al ., ; Tateno et al ., ; Rittmann et al ., ; Youn et al ., ; ).…”