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Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers.

ABSTRACT: One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon sequencing analysis was carried out on milk, final products, and fouling samples taken from dairy concentrate production lines. The analysis of these samples revealed the presence of DNA from a broad range of bacterial taxa, including a majority of mesophiles and a minority of (thermophilic) spore-forming bacteria. Enrichments of fouling samples at 55°C showed the accumulation of predominantly Brevibacillus and Bacillus, whereas enrichments at 65°C led to the accumulation of Anoxybacillus and Geobacillus species. Bacterial population analysis of biofilms grown using fouling samples as an inoculum indicated that both Anoxybacillus and Geobacillus preferentially form biofilms on surfaces at air-liquid interfaces rather than on submerged surfaces. Three of the most potent biofilm-forming strains isolated from the dairy factory industrial samples, including Geobacillus thermoglucosidans, Geobacillus stearothermophilus, and Anoxybacillus flavithermus, have been characterized in detail with respect to their growth conditions and spore resistance. Strikingly, Geobacillus thermoglucosidans, which forms the most thermostable spores of these three species, is not able to grow in dairy intermediates as a pure culture but appears to be dependent for growth on other spoilage organisms present, probably as a result of their proteolytic activity. These results underscore the importance of abiotic and microbiotic factors in niche colonization in dairy factories, where the presence of thermophilic sporeformers can affect the quality of end products.

SUBMITTER: Zhao Y

PROVIDER: S-EPMC3754176 | biostudies-other | 2013 Sep

REPOSITORIES: biostudies-other

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Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers.

Zhao Yu Y Caspers Martien P M MP Metselaar Karin I KI de Boer Paulo P Roeselers Guus G Moezelaar Roy R Nierop Groot Masja M Montijn Roy C RC Abee Tjakko T Kort Remco R

Applied and environmental microbiology 20130712 18

One of the major concerns in the production of dairy concentrates is the risk of contamination by heat-resistant spores from thermophilic bacteria. In order to acquire more insight in the composition of microbial communities occurring in the dairy concentrate industry, a bar-coded 16S amplicon sequencing analysis was carried out on milk, final products, and fouling samples taken from dairy concentrate production lines. The analysis of these samples revealed the presence of DNA from a broad range ...[more]

PMID: 23851093

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Dataset Information

Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers.

Publications

Abiotic and microbiotic factors controlling biofilm formation by thermophilic sporeformers.

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