Comparative proteomics of uropathogenic Escherichia coli during growth in human urine identify UCA-like (UCL) fimbriae as an adherence factor involved in biofilm formation and binding to uroepithelial cells

Uropathogenic Escherichia coli (UPEC) are the primary cause of urinary tract infection (UTI) in humans. For the successful colonisation of the human urinary tract, UPEC employ a diverse collection of secreted or surface-exposed virulence factors including toxins, iron acquisition systems and adhesins. In this study, a comparative proteomic approach was utilised to define the UPEC pan and core surface proteome following growth in pooled human urine. Identified proteins were investigated for subcellular origin, prevalence and homology to characterised virulence factors. Fourteen core surface proteins were identified, as well as eleven iron uptake receptor proteins and four distinct fimbrial types, including type 1, P, F1C/S and a previously uncharacterised fimbrial type, designated UCA-like (UCL) fimbriae in this study. These pathogenicity island (PAI)-associated fimbriae are related to UCA fimbriae of Proteus mirabilis, associated with UPEC and exclusively found in members of the E. coli B2 and D phylogroup. We further demonstrated that UCL fimbriae promote significant biofilm formation on abiotic surfaces and mediate specific attachment to exfoliated human uroepithelial cells. Combined, this study has defined the surface proteomic profiles and core surface proteome of UPEC during growth in human urine and identified a new type of fimbriae that may contribute to UTI

Mesophilic to thermophilic conditions in codigestion of sewage sludge and OFMSW: evaluation of effluent stability using dynamic respirometric index (DRI) and biochemical methane potential (BMP).

The paper deals with the change from the mesophilic to thermophilic conditions in the codigestion process applied to secondary sludge from a biological nutrients removal (BNR) together with the organic fraction of municipal solid waste (OFMSW) or biowaste. The first part of the study was carried out at pilot scale in a 0.38 nr' pilot scale plant, in order to evaluate the process behaviour during short-time meso-thermo passage and the relative yield increase, in the second part, the same set of operational conditions was applied to a full scale 2000 m 3 digester: both pilot and full scale trials evidenced the same behaviour and results. The thermophilic range of temperature showed a general increase of performance of about 50% in terms of biogas yields and allowed for a better stabilisation of the effluent (digestate). In order to evaluate this aspect, both the aerobic and anaerobic rate of stability was evaluated: the effective rate of stabilisation of the digested material by means of aerobic (Dynamic Respirometric Index), and anaerobic batch tests (Biochemical Methane Potential) was determined. Preliminary tests on the effluents originated from three plants showed a DRI lower than 1000 mgO 2/kgVSh which is the minimum value required for a stable compost following the Italian regulation system, and an average SGP of 0,15-0,30 m 3/kgVS which demonstrated a partial conversion of the organic matter into biogas