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We report the results of the monitoring of resistance to ampicillin, vancomycin, and teicoplanin in enterococci by an Italian network of clinical microbiology laboratories. A total of 16,226 strains were analyzed; 9,169 of these strains were Enterococcus faecalis, 913 were Enterococcus faecium, and 6,144 were Enterococcus species. The average rate of resistance to ampicillin was 1.9% (range, 0-6.5%) for E. faecalis and 70% (range, 33.3%-98.7%) for E. faecium; the average rate of resistance to vancomycin was 1.1% (range, 0.1%-2%) for E. faecalis and 8.5% (range, 0-36.1%) for E. faecium; and the average rate of resistance to teicoplanin was 0.8% (range, 0-2.4%) for E. faecalis and 8.7% (range, 0-36.1%) for E. faecium.

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This study evaluated the efficacy of lysozyme in winemaking to control lactic acid bacteria (LAB). In a winery vinification, indigenous LAB were partially and completely inhibited when lysozyme was added to red and white grape must respectively. This result was confirmed by using two selected strains of Lactobacillus brevis and Oenococcus oeni to contaminate the grape must. In the red wine microvinification, the cell population decreased only temporarily and malolactic fermentation terminated at different times, depending on the grape must pH and lysozyme dosage. In the white wine microvinification, cell mortality rates differed according to lysozyme dosage rather than pH values. During the fermentation, lysozyme activity was stable or decreased, depending on the absence or presence of grape must respectively. The study highlighted that lysozyme efficacy is strongly affected by the type of vinification.

Full-fledged proteomic analysis of bioactive wheat amylase inhibitors by a 3-D analytical technique: Identification of new heterodimeric aggregation statesWheat proteinaceous a-amylase inhibitors (a-AIs) are increasingly investigated for their agronomical role as natural defence molecules of plants against the attack of insects and pests, but also for their effects on human health. The wheat genomes code for several bioactive a-AIs that share sequence homology, but differ in their specificity against a-amylases from different species and for their aggregation states. Wheat a-AIs are traditionally classified as belonging to the three classes of tetrameric, homodimeric and monomeric forms, each class being constituted by a number of polypeptides that display different electrophoretic mobilities. Here we describe a proteomic approach for the identification of bioactive a-AIs from wheat and, in particular, a 3-D technique that allows to best identify and characterize the dimeric fraction. The technique takes advantage of the thermal resistance of a-AIs (resistant to T . 707C) and consists in the separation of protein mixtures by 2-D polyacrylamide/starch electrophoresis under nondissociating PAGE (ND-PAGE, first dimension) and dissociating (urea-PAGE or U-PAGE second dimension) conditions, followed by in-gel spontaneous reaggregation of protein complexes and identification of the a-amylase inhibitory activity (antizymogram, third dimension) using enzymes from human salivary glands and from the larvae of Tenebrio molitor coleopter (yellow mealworm). Dimeric a-AIs from Triticum aestivum (bread wheat) were observed to exist as heterodimers. The formation of heterodimeric complexes was also confirmed by in vitro reaggregation assays carried out on RP-HPLC purified wheat dimeric a-AIs, and their bioactivity assayed by antizymogram analysis. The present 3-D analytical technique can be exploited for fast, full-fledged identification and characterization of wheat a-AIs.

The epidemiology of vancomycin-resistant enterococci (VRE) was studied in a large tertiary-care hospital in northern Italy from February 1993 to December 1999. Sixteen cases of bacteraemic and 17 cases of nonbacteraemic active infections caused by VRE were recorded. Fifteen of the bacteraemic and four of the nonbacteraemic infections occurred in patients in the haematology department, while the remainder were registered in other departments of the same hospital. Active surveillance for the presence of VRE in stools led to identification of 51 noninfected carriers over the 1994-1999 period; of these, 32 were haematology patients and the remainder were patients admitted to other departments. All VRE isolates carried the vanA gene. Forty-one Enterococcus faecium isolates and eight Enterococcus faecalis isolates collected in the 1993-1996 period were typed by pulsed-field gel electrophoresis. Twenty-nine isolates of Enterococcus faecium shared either indistinguishable or strictly or possibly related patterns. Of these, 26 were isolated from patients in the haematology department. This is believed to be the first study on the epidemiology of VRE carried out in a large hospital in Italy over a period of several consecutive years. It reports an increase in VRE due to the epidemic spread of genetically related strains and sporadic infections or colonisation by unrelated VRE. It also documents the success of surveillance and of the

A previously-developed method for protein recovery from wine has been applied to beer and beer foam samples. The method involves the complexation of proteins with dodecyl sulfate (added as sodium salts) and subsequently the insolubilization of the protein-detergent complexes by addition of potassium ions (added as KCl). The protocol allows preparation of proteins from a few hundred microliters of beverage in a few minutes. The precipitated proteins are free from interfering materials and are directly utilizable for quantitative and electrophoretic assays.