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We report here the closed genome of Clostridium pasteurianum ATCC 6013, a saccharolytic, nitrogen-fixing, and spore-forming Gram-positive obligate anaerobe. The organism is of biotechnological interest due to the production of solvents (butanol and 1,3-propanediol) but can be associated with food spoilage. The genome comprises a total of 4,351,223 bp.

Germination, the process by which dormant endospores return to vegetative growth, is a critical process in the life cycle of the notorious pathogen Clostridium botulinum. Crucial is the degradation by hydrolytic enzymes of an inner peptidoglycan spore layer termed the cortex. Two mechanistically different systems of cortex lysis exist in spores of Clostridium species. C. botulinum ATCC 3502 harbours the Bacillus-like system of SleB, CwlJ and YpeB cortex lytic enzymes (CLEs). Through the construction of insertional gene knockout mutants in the sleB, cwlJ and ypeB genes of C. botulinum ATCC 3502 and the production of spores of each mutant strain, the effect on germination was assessed. This study demonstrates a reduced germination efficiency in spores carrying mutations in either sleB or ypeB with an approximate 2-fold reduction in heat resistant colony forming units (CFU/OD600) when plated on rich media. This reduction could be restored to wild-type levels by removing the spore coat and plating on media supplemented with lysozyme. It was observed that cwlJ spores displayed a similar germination efficiency as wild-type spores (P > 0.05). An optimal germinant commixture was identified to include a combination of l-alanine with sodium bicarbonate as it resulted in a 32% drop in OD600, while the additional incorporation of l-lactate resulted in a 57% decrease. Studies of the germination efficiency of spores prepared from all three CLE mutants was performed by monitoring the associated decrease in optical density but a germination defect was not observed in any of the CLE mutant strains. This was likely due to the lack of specificity of this particular assay. Taken together, these data indicate that functional copies of SleB and YpeB, but not CwlJ are required for the optimal germination of the spores of C. botulinum ATCC 3502.

Mutant strains of Clostridium botulinum ATCC 3502 were generated using the ClosTron in four genes (CBO1789, CBO1790, CBO3048, CBO3145) identified as encoding α/β-type SASP homologues. The spores of mutant strains in which CBO1789 or CBO1790 was inactivated demonstrated a significant increase in sensitivity to the damaging agent nitrous acid (P0.01), a phenotype that was partially restored to wild-type in complementation studies. In contrast to nitrous acid, the spores of the CBO1789 and CBO1790 mutants showed no change in their resistance to formaldehyde and hydrogen peroxide (P0.05), two other chemicals commonly used as components of disinfection regimes. These data indicate that the SASPs CBO1789 or CBO1790 play a significant role in resistance to nitrous acid, but not in resistance to formaldehyde or hydrogen peroxide.

Part 1 Risk assessment and management in the food chain: Introduction Detecting pathogens in food Modeling the growth, survival and death of microbial pathogens in foods Risk assessment and pathogen management Emerging foodborne pathogens and the food industry Pathogen control in primary production: meat, dairy and eggs Pathogen control in primary production: crop foods Pathogen control in primary production: fisheries and aquaculture Pathogen control in primary production: bivalve shellfish Hygienic plant design Hygienic equipment design Sanitation Safe process design and operation The effective implementation of HACCP systems in food processing Good practice for food handlers and consumers. Part 2 Bacterial hazards: Preservation principles and technologies: Pathogenic Escherichia coli Salmonella Listeria monocytogenes Campylobacter and Arcobacter Other Gram-negative bacterial pathogens Staphylococcus aureus and other pathogenic Gram positive cocci Pathogenic Clostridium species Pathogenic Bacillus species. Part 3 Other agents of foodborne disease: Hepatitis viruses and emerging viruses Parasites: Cryptosporidium, Giardia, Cyclospora, Entamoeba histolytica, Toxoplasma gondii and pathogenic free-living amoebae (Acanthamoeba spp. and Naegleria fowleri) as foodborne pathogens Foodborne helminth infections Toxigenic fungi Mycobacterium paratuberculosis Transmissible Spongiform Encephalopathy (Prion Disease) Histamine fish poisoning: new information to control a common seafood safety issue Gastroenteritis viruses.

Since consumers' images reflect to some extent actions taken by marketers in dealing with many marketing variables, it is frequently desirable to determine if these images have patterns. For this purpose, the Friedman two-way analysis of variance by ranks may be useful, especially when the data are ordinal and when each respondent answers questions on a variety of products, product attributes, or brands. The ordinal nature of the data precludes the use of parametric statistical tools such as analysis of variance, and the need to compare a variety of data generated by each respondent precludes the use of certain nonparametric statistical tools, such as chi-square, since the requirement of independent samples is not met.

Retailers, because of their close association with the public, have historically been described as an excellent source of information about consumers. Interviews with consumers and appliance retailers reveal several interesting retailer misconceptions of consumers which may lead to ill-considered marketing strategies.