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Organophosphorus hydrolase (OPH) hydrolyzes organophosphorus esters. We constructed the yeast-displayed OPH using Flo1p anchor system. In this system, the N-terminal region of the protein was fused to Flo1p and the fusion protein was displayed on the cell surface. Hydrolytic reactions with paraoxon were carried out during 24 h of incubation of OPH-displaying cells at 30°C. p-Nitrophenol produced in the reaction mixture was detected by HPLC. The strain with highest activity showed 8-fold greater OPH activity compared with cells engineered using glycosylphosphatidylinositol anchor system, and showed 20-fold greater activity than Escherichia coli using the ice nucleation protein anchor system. These results indicate that Flo1p anchor system is suitable for display of OPH in the cell surface-expression systems.

Cell surface display of proteins/peptides, in contrast to the conventional intracellular expression, has many attractive features. This arming technology is especially effective when yeasts are used as a host, because eukaryotic modifications that are often required for functional use can be added to the surface-displayed proteins/peptides. A part of various cell wall or plasma membrane proteins can be genetically fused to the proteins/peptides of interest to be displayed. This technology, leading to the generation of so-called "arming technology", can be employed for basic and applied research purposes. In this article, we describe various strategies for the construction of arming yeasts, and outline the diverse applications of this technology to industrial processes such as biofuel and chemical productions, pollutant removal, and health-related processes, including oral vaccines. In addition, arming technology is suitable for protein engineering and directed evolution through high-throughput screening that is made possible by the feature that proteins/peptides displayed on cell surface can be directly analyzed using intact cells without concentration and purification. Actually, novel proteins/peptides with improved or developed functions have been created, and development of diagnostic/therapeutic antibodies are likely to benefit from this powerful approach. [ABSTRACT FROM AUTHOR]

Xylose isomerase (XI) is a key enzyme in the conversion of d-xylose, which is a major component of lignocellulosic biomass, to d-xylulose. Genomic analysis of the bacterium Clostridium cellulovorans revealed the presence of XI-related genes. In this study, XI derived from C. cellulovorans was produced and displayed using the yeast cell-surface display system, and the xylose assimilation and fermentation properties of this XI-displaying yeast were examined. XI-displaying yeast grew well in medium containing xylose as the sole carbon source and directly produced ethanol from xylose under anaerobic conditions. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 346-351, 2013 [ABSTRACT FROM AUTHOR]

Candida albicans is normally present in nearly all humans but can cause fatal diseases in immunocompromised patients. The agglutinin-like sequence ( ALS) gene family of C. albicans has been suggested to be important for biofilm formation on medical devices. Here, we cloned all ALS genes and determined the binding properties of their gene products by cell surface engineering of Saccharomyces cerevisiae. Most of the ALS homologues had the ability to bind polypropylene, borosilicate glass and polyvinyl chloride, which are often used as materials in medical devices. However, ALS homologues were not able to bind polyurethane, polymethyl methacrylate, polytetrafluoroethylene or titanium. These findings will aid in the development of biofilm-resistant medical devices. [ABSTRACT FROM AUTHOR]

Laminarin is the algal storage glucan and represents up to 35% of the dry weight of brown macroalgae. In this study, a novel laminarinase, Gly5M, was first found using focused proteome analysis of a laminarin-assimilating marine bacterium, Saccharophagus degradans , and the encoding gene was isolated. A Gly5M-displaying yeast strain was prepared with the cell surface display system using Saccharomyces cerevisiae . It showed a laminarin-degrading activity on the cell surface and caused the dominant accumulation of gentiobiose. The obtained gentiobiose was converted into glucose and could be assimilated by an Aspergillus aculeatus β-glucosidase (BG)-displaying yeast strain. When Gly5M- and BG-displaying yeasts were anaerobically cultivated together in fermentation medium containing 20 g/L laminarin as a sole carbon source, the coculture system with the combination of optimized ratios of the 2 yeast strains directly produced 5.2 g/L ethanol. This coculture system of the 2 engineered yeast strains would be a platform for the use of laminarin and contribute to the complete utilization of brown macroalgae. [ABSTRACT FROM AUTHOR]

Three β-glucosidase- and two endoglucanase-encoding genes were cloned from Aspergillus oryzae, and their gene products were displayed on the cell surface of the sake yeast, Saccharomyces cerevisiae GRI-117-UK. GRI-117-UK/pUDB7 displaying β-glucosidase AO090009000356 showed the highest activity against various substrates and efficiently produced ethanol from cellobiose. On the other hand, GRI-117-UK/pUDCB displaying endoglucanase AO090010000314 efficiently degraded barley β-glucan to glucose and smaller cellooligosaccharides. GRI-117-UK/pUDB7CB codisplaying both β-glucosidase AO090009000356 and endoglucanase AO090010000314 was constructed. When direct ethanol fermentation from 20 g/l barley β-glucan as a model substrate was performed with the codisplaying strain, the ethanol concentration reached 7.94 g/l after 24 h of fermentation. The conversion ratio of ethanol from β-glucan was 69.6% of the theoretical ethanol concentration produced from 20 g/l barley β-glucan. These results showed that sake yeast displaying A. oryzae cellulolytic enzymes can be used to produce ethanol from cellulosic materials. Our constructs have higher ethanol production potential than the laboratory constructs previously reported. [Copyright &y& Elsevier]