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This study examines the latest advancements in the field of Microbial ElectroSynthesis (MES) and reports a unique sustainability and economic assessment for the production of five alternative compounds (formic, acetic, propionic acids; methanol and ethanol). Different chemical production conditions were compared by modelling a 1000 t per year production plant. Three sustainability indicators; net energy consumption (NEC), energy gain (EG) and global warming ratio (GWR), were used; along with three economic indicators: production cost, pay-back period and discounted cash flow rate of return. NEC analysis revealed substantial energy requirements in the MES reactor and rectification unit. The former due to the energy required to synthesise CO 2 to longer chains and the later due to increased water molecules formed during synthesis. EG values suggested that producingformic acid and methanol using MES were lower than conventional processes. MES was shown to use more carbon dioxide for methanol, ethanol and formic acid synthesis than those produced. The economic analysis showed that formic acid and ethanol had a long pay-back period of 15 years. However, production costs were found to be competitive with the market only for formic acid (0.30 £/kg) and ethanol (0.88 £/kg). Moreover, high returns were evaluated for formic acid (21%) and ethanol (14%) compared to the minimum requirements of the industry (11.60%) making these products economically attractive. Our findings reveal insights about the use and scale up of MES for a sustainable and economically viable chemical production process. [ABSTRACT FROM AUTHOR]

Abstract: Defects in glycosylation are becoming increasingly associated with a range of human diseases. In some cases, the disease is caused by the glycosylation defect, whereas in others, the aberrant glycosylation may be a consequence of the disease. The implementation of highly sensitive and rapid mass spectrometric screening strategies for profiling the glycans present in model biological systems is revealing valuable insights into disease phenotypes. In addition, glycan screening is proving useful in the analysis of knock-out mice where it is possible to assess the role of glycosyltransferases and glycosidases and what function they have at the cellular and whole organism level. In this study, we analysed the effect of insulin on the glycosylation of 3T3-L1 cells and the effect of insulin resistance on glycosylation in a mouse model. Transcription profiling of 3T3-L1 cells treated with and without insulin revealed expression changes of several glycogenes. In contrast, mass spectrometric screening analysis of the glycans from these cells revealed very similar profiles suggesting that any changes in glycosylation were most likely on specific proteins rather than a global phenomenon. A fat-fed versus carbohydrate-fed mouse insulin resistant model was analysed to test the consequences of chronic insulin resistance. Muscle and liver N-glycosylation profiles from these mice are reported. [Copyright &y& Elsevier]

Abstract: The MUC6 mucin was originally isolated from stomach mucus and is one of the major secreted mucins of the digestive tract. A full-length cDNA has not been isolated for this large molecule (greater than 15 kb) and it remains poorly studied. To circumvent the lack of reagents for investigating MUC6, we isolated a cDNA clone from a human fetal pancreatic duct cDNA library that encodes 282 amino acids of the MUC6 tandem repeat. A blast search with the sequence of this cDNA clone showed 90% homology with the original MUC6 (L07517) derived from a human stomach cDNA library and 95% homology both with AK096772, a MUC6-related protein isolated from a human prostate cDNA library and the human genome project clone AC083984. The MUC6 partial cDNA clone isolated from fetal pancreas was inserted into an epitope-tagged MUC1 mucin molecule in place of the native tandem repeat. This chimeric mucin was expressed in human pancreatic (Panc1) and colon (Caco2) carcinoma cell lines and purified for analysis of O-glycosylation by fast atom bombardment mass spectrometry (FAB-MS). The FAB-MS spectra showed O-glycans that had been detected previously on chimeric mucins carrying different tandem repeats, though the spectra for MUC1F/6TR mucins expressed in the Panc1 and Caco2 cells were very different. There was a paucity of O-glycosylation in Panc1 cells in comparison to Caco2 cells where many more structures were evident, and the most abundant glycans in Panc1 cells were sialylated. [Copyright &y& Elsevier]