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Identification of bacteria in aquatic and environmental applications, for monitoring purposes and research, for health assessments and therapy considerations of farmed and free-living aquatic organisms, still relies on conventional phenotypic and biochemical protocols. Although molecular techniques based on DNA amplification and sequencing are finding ways into diagnostic laboratories, they are time-consuming, costly and difficult in the case of multiplex assays. Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) is a rapid and accurate proteomic method reliable for identification of unknown bacteria to the genus and species level. Upon extension of databases, it will certainly find its position in environmental sciences. The paper presents an overview of the principle of the method, its effectiveness in comparison with conventional and molecular identification procedures, and applicability on environmental and aquatic isolates, discussing its advantages and shortcomings, as well as possible future implementations. [ABSTRACT FROM AUTHOR]

Due to high anthropogenic pressures, science-based coastal management required to ensure the sustainable use of coastal areas highly depends on environmental indicators used for decision-making. In this paper, we argue for the inclusion of Vibrio spp. abundance as a supplemental indicator of water quality for science-based coastal management by examining the environmental and bacterial indicators at a fish farm and a control site in Mali Ston Bay in the Adriatic Sea. Unexpectedly, heterotrophic bacteria, enterococci and Vibrio spp. were more abundant in the cold season, while E. coli and total coliforms, following a more traditional pattern, were more abundant in the warm season. Each of the currently used indicators has a specific purpose: heterotrophic bacteria indicate the presence of both nonpathogenic and pathogenic bacteria, while enterococci are pathogenic bacteria indicating fecal pollution. Vibrio spp. abundance additionally represents a non-fecal bacteria that can cause vibriosis in humans and aquatic organisms. Since vibriosis is the leading cause of disease-related fish mortality in aquaculture, pathogenic Vibrio spp. have large health and economic implications. These implications, as well as the added interpretative value when compared to other bacterial indicators, make Vibrio spp. abundance a good candidate as a water quality indicator. Significant dependence of the abundance on depth further differentiates Vibrio spp. from other indicators, thus bolstering the candidacy - especially in aquaculture areas. Before inclusion of any Vibrio spp. indicators into legislature, further research is needed particularly into (i) abundance thresholds characterizing water quality, and (ii) identification of species whose abundance should be monitored for best estimate of the disease risks. [Display omitted] • Analysis of environmental and bacterial indicators revealed no difference between fish farm and control. • Contrary to expectations, heterotrophic bacteria and Vibrio spp. thrived in the cold season. • Vibrio spp. abundance provides additional information on water quality and health risks. • Vibrio spp. could indicate poor water quality, even when other indicators suggest the quality is excellent. [ABSTRACT FROM AUTHOR]

S-layers represent the simplest biological membranes developed during the evolution and are one of the most abundant biopolymers on Earth. Current fundamental and applied research aim to reveal the chemical structure, morphogenesis and function of S-layer proteins (Slps). This is the first paper that describes the Slps of certain Lactobacillus brevis strain isolated from sauerkraut. The whole genome sequence (WGS) analysis of the L. brevis SF9B strain uncovered three genes encoding the putative Slps, but merely one, identified as similar to the SlpB of L. brevis ATCC 14869, was expressed. Slp-expressing SF9B cells exhibited increased survival in simulated gastrointestinal (GI) conditions and during freeze-drying. Their survival in stress conditions was additionally enhanced by microencapsulation, especially when using alginate with gelatine as a matrix. Thus prepared cells were subjected to simulated GI conditions and their mortality was only 0.28 ± 0.45 log CFU/mL. Furthermore, a correlation between the high surface hydrophobicity and the remarkable aggregative capacity of SF9B strain was established. The results indicate a prominent role of Slps in adhesion to mucin, extracellular matrix (ECM) proteins, and particularly to Caco-2 cells, where the removal of Slps utterly abolished the adhesiveness of SF9B cells for 7.78 ± 0.25 log CFU/mL. [ABSTRACT FROM AUTHOR]