Coaggregation between Rhodococcus and Acinetobacter strains isolated from the food industry

Abstract

In this study coaggregation interactions between Rhodococcus and Acinetobacter strains isolated from food processing surfaces were characterized. Rhodococcus sp. MF3727 formed intra-generic coaggregates with Rhodococcus sp. MF3803 and inter-generic coaggregates with two strains of Acinetobacter calcoaceticus (MF3293, MF3627). Stronger coaggregation between Acinetobacter calcoaceticus MF3727and Rhodococcus sp. MF3293 was observed following growth in batch-culture at 30 °C as opposed to 20 °C, after growth in Tryptic Soy broth as compared to liquid R2A medium, and between cells in exponential and early stationary phase as compared to late stationary phase. The coaggregation ability of Rhodococcus sp. MF3727 was maintained even after heat and Proteinase K treatment, suggesting the ability to coaggregate was protein independent while the coaggregation determinants of the other strains involved proteinaceous cell-surface-associated polymers.Coaggregation was stable at pH 5-9. The mechanisms of coaggregation among Acinetobacter and Rhodococcus strains bare similarity to that displayed by coaggregating bacteria of oral and freshwater origin, with respect to binding between proteinaceous and nonproteinaceous determinants and the effect of environmental factors on coaggregation.Coaggregation may contribute to biofilm formation on industrial food surfaces, which can protect bacteria against cleaning and disinfection.

Characteristics of N-Acylhomoserine Lactones Produced by Hafnia alvei H4 Isolated from Spoiled Instant Sea Cucumber

“…Pesudomonas is widely present in chill-stored proteinaceous raw foods, vacuum-packed food and aquatic food products, but has also been isolated from spoiled pasteurized milk [6], whereas Hafnia is often found in vacuum-packed, refrigerated spherical fish paste and fresh meat [3,30]. Acinetobacter is found in brand beef and on food processing surfaces [31,32]. Quorun sensing system has been shown to play a role in bacteria-mediated food spoilage, especially those mediated by gram-negative bacteria, and the production of AHLs is thought to be an important contributing factor.…”

Ralstonia insidiosa induces cell aggregation of Listeria monocytogenes

“…These outcomes indicated that the induced aggregation of L. monocytogenes was dependent on cell to cell contact between cells of the two species, a notion that was consistent with the data of our microscopic examinations. In a recent study, Møretrø and colleagues demonstrated that coaggregation interactions between Rhodococcus and Acinetobacter strains isolated from food-processing surfaces were not sensitive to heat and Proteinase K treatment, suggesting protein independent aggregation, whereas the coaggregation determinants of the other strains involved proteinaceous cell-surface-associated polymers (Møretrø, Sharifzadeh, Langsrud, Heir, & Rickard, 2015).…”

Advanced Rhodococcus Biocatalysts for Environmental Biotechnologies

“…TiBP resembled a homodimeric dihydrolipoamide dehydrogenase, leading to bonds between rhodococcal cells and minerals via hydrophobic interactions [112][113][114]. In reference [115], treatment with proteinase K resulted in a reduced rhodococcal ability to co-aggregate with Acinetobacter calcoaceticus, although not all Rhodococcus strains tested were sensitive to this procedure. Apparently, protein adhesins of rhodococci are strain-specific and are involved in the adhesion to certain sites on biotic and abiotic surfaces.…”