The PM has a decreased expression of 19 and 42 of the 99 genes that encode for cellulosomal components in standard and Vorinostat molecular weight Populus hydrolysate

media, respectively (Additional file 4). The statistically significant decreased expression in cellulosome genes by the PM may be an attempt to conserve energy since the cells were adapted in media containing cellobiose and soluble glucans present from the hydrolysate. It has been hypothesized that the downregulation of the cellulosome on soluble substrate such as cellobiose occurs via Dibutyryl-cAMP datasheet catabolite repression [42]. The PM has a synonymous SNP at codon 415 in RsgI6 (Cthe_2119) which is an anti-σI factor involved in regulating the expression of cellulosomal genes in the presence of xylans and cellulose [17]. It is possible that this mutation changes the specificity of the anti-σI factor and reduces the expression of the cellulosomal genes over and above the reduction that would be achieved by catabolite repression alone. The PM has lower expression than the WT of 31 and 54 genes that encode for cell envelope

proteins in standard and Populus hydrolysate medium (Additional file 4). The PM also downregulated 21 and 50 genes that encode for cell motility in standard and Populus hydrolysate media compared to the WT. It has been proposed that the σD in B. PX-478 mw subtilis controls flagellin production and possibly has a role in the expression of the methyl-accepting chemotaxis proteins [31]. Sigma factor σD (Cthe_0495) is downregulated in the PM compared to the WT in standard and Populus hydrolysate media by 3-fold and 10-fold at the mid-log time point (Table 1) and may cause the decrease in cell motility genes. The PM also downregulated 12 genes that encode Megestrol Acetate for various inorganic ion transport and metabolism proteins compared to the WT in standard medium and upregulates 17 genes in 10% v/v Populus hydrolysate medium.

However, the downregulated genes do not belong to any specific pathway. The change in expression may be due to the downregulation of inorganic ion transport and metabolism genes in the standard versus Populus hydrolysate media comparison below. The PM also downregulated 26 genes in the miscellaneous category compared to the WT in standard medium. Beyond a simple conservation of cellular resources, the benefits of reducing the expression level of genes in these categories are unclear. Hydrolysate comparison The Populus hydrolysate concentration comparison represents the difference in gene expression for various hydrolysate concentrations within a given strain.