Sulfate assimilation pathway intermediate phosphoadenosine 5′-phosphosulfate acts as a signal molecule affecting production of curli fibres in Escherichia coli

Abstract

The enterobacterium Escherichia coli can utilize a variety of molecules as sulfur sources, including cysteine, sulfate, thiosulfate and organosulfonates. An intermediate of the sulfate assimilation pathway, adenosine 59-phosphosulfate (APS), also acts as a signal molecule regulating the utilization of different sulfur sources. In this work, we show that inactivation of the cysH gene, leading to accumulation of phosphoadenosine 59-phosphosulfate (PAPS), also an intermediate of the sulfate assimilation pathway, results in increased surface adhesion and cell aggregation by activating the expression of the curli-encoding csgBAC operon. In contrast, curli production was unaffected by the inactivation of any other gene belonging to the sulfate assimilation pathway. Overexpression of the cysH gene downregulated csgBAC transcription, further suggesting a link between intracellular PAPS levels and curli gene expression. In addition to curli components, the Flu, OmpX and Slp proteins were also found in increased amounts in the outer membrane compartment of the cysH mutant; deletion of the corresponding genes suggested that these proteins also contribute to surface adhesion and cell surface properties in this strain. Our results indicate that, similar to APS, PAPS also acts as a signal molecule, albeit with a distinct mechanism and role: whilst APS regulates organosulfonate utilization, PAPS would couple availability of sulfur sources to remodulation of the cell surface, as part of a more global effect on cell physiology.

Differences in Gene Expression Profiles between Early and Late Isolates in Monospecies Achromobacter Biofilm

“…Methionine sulfoxide reductase genes MsrA and MsrB were also highly upregulated (756 and 201 times, respectively) (Table 2 and Figure 1). Sulfur metabolism has been connected to biofilm metabolism in Staphylococcus aureus [25], to production of an adhesin in Escherichia coli [26], and with iron acquisition in P. aeruginosa [27]. The function of sulfur metabolism in chronic Achromobacter infections remains to be elucidated, but the pivotal upregulation suggests a key adaptive role of sulfur metabolism in late stage CF.…”

Acid Evolution of Escherichia coli K-12 Eliminates Amino Acid Decarboxylases and Reregulates Catabolism

“…Also downregulated were cysACD (sulfate transport) and ariR (regulator of acid resistance). Inactivation of these operons is associated with increased cell aggregation, which could contribute to the increased acid fitness in these strains (34,35).…”

“…Also downregulated were cysACD (sulfate transport) and ariR (regulator of acid resistance). Inactivation of these operons is associated with increased cell aggregation, which could contribute to the increased acid fitness in these strains (34,35).Strain F9-2, whose genome contains a deletion of the anaerobic regulator fnr, showed downregulation of a number of genes normally upregulated by Fnr under low-oxygen conditions (25,28). The downregulated genes include dmsABC (dimethyl sulfoxide reductase), frdABCD (fumarate reductase), hybABO (Hyd-2), nikABCDE (nickel ABC transporter), and nrfAC (formate-dependent nitrite reductase).…”

Characterization of the phosphate-specific transport system inCronobacter sakazakiiBAA-894

“…Inactivation of cysH encoding phosphoadenosine‐phosphosulphate reductase could increase intracellular phosphoadenosine‐phosphosulphate concentration, which enhanced surface adhesion (Rossi et al . ). Compared to BAA‐894 cells grown in LP media, the homologue gene of cysH showed log2 Ratio of 4·17.…”