13C-His-Cβ centered contiguous 13C-fragments in T. reesei. Fractions of 13C-His-Cβ centered contiguous 13C-fragments in T. reesei in different genetic, wild type (wt) and Δcre1 mutant. Cultures were grown on glucose (glucose repressed) or sorbitol (derepressed). Sorbitol grown cultures were grown with or without induction of cellulase gene expression by the addition of sophorose to some cultures. His-Cβ f(1) denotes fragments with C-C bonds cleaved on both sides of Cβ, His-Cβ f(2) and f(2*) denote fragments with Cβ-Cα and Cβ-Cγ preserved, respectively, and His- Cβ f(3) denotes fragments were both bonds are intact. Error bars represent ± SEM.