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Palaeoenvironmental reconstruction from Eemian insect remains at Ejstrup, Denmark: Evidence for a riverine settingNARA Subscribed
The freshwater environments of the Eemian are well documented, although mostly focussed on lakes. Here, we present results from lake sediments of dark grey, laminated, organic‐rich medium sand, on top of very dark grey gyttja at the site of Ejstrup, west of Kolding, Denmark. Based on pollen counts, the sediments were biostratigraphically classified as mid‐Eemian. Despite the lake deposition, the assemblage of aquatic insect su...
The decline of mussel aquaculture in the European Union: causes, economic impacts and opportunitiesNARA Subscribed
In contrast to the increasing aquaculture production of mussels worldwide, production in the European Union (EU) has shown a decreasing trend over the last two decades. Aquaculture production of mussels in the EU peaked in the late 1990s at more than 600 000 tonnes; by 2016, production volume had dropped by 20% to 480 000 tonnes. As mussel production represents more than ⅓ of EU aquaculture production, this decrease is an impo...
The International Energy Agency Technology Collaboration Programme for Ocean Energy Systems (OES) initiated the OES Wave Energy Conversion Modelling Task, which focused on the verification and validation of numerical models for simulating wave energy converters (WECs). The long-term goal is to assess the accuracy of and establish confidence in the use of numerical models used in design as well as power performance assessment o...
Summary In the present review, we describe and compare the molecular mechanisms that are involved in the regulation of biofilm formation by P seudomonas putida, P seudomonas fluorescens, P seudomonas aeruginosa and B urkholderia cenocepacia . Our current knowledge suggests that biofilm formation is regulated by cyclic diguanosine‐5′‐monophosphate ( c‐di‐GMP ), small RNAs ( sRNA ) and quorum sensing ( QS ) in all these bacteria...
Summary Although the growth of bacteria has been studied for more than a century, it is only in recent decades that surface‐associated growth has received attention. In addition to the well‐characterized biofilm and swarming lifestyles, bacteria can also develop as micro‐colonies supported by structured environments in both food products and the GI tract. This immobilized mode of growth has not been widely studied. To develop...
Mating between relatives often results in negative fitness consequences or inbreeding depression. However, the expression of inbreeding in populations of wild cooperative mammals and the effects of environmental, maternal and social factors on inbreeding depression in these systems are currently not well understood. This study uses pedigree‐based inbreeding coefficients from a long‐term study of meerkats ( Suricata suricatta )...
Influence of putative exopolysaccharide genes on Pseudomonas putida KT2440 biofilm stabilityNARA Subscribed
Summary We report a study of the role of putative exopolysaccharide gene clusters in the formation and stability of Pseudomonas putida KT2440 biofilm. Two novel putative exopolysaccharide gene clusters, pea and peb , were identified, and evidence is provided that they encode products that stabilize P. putida KT2440 biofilm. The gene clusters alg and bcs , which code for proteins mediating alginate and cellulose biosynthesis, w...
HD‐GYP domain proteins regulate biofilm formation and virulence in Pseudomonas aeruginosaNARA Subscribed
Summary HD‐GYP is a protein domain involved in the hydrolysis of the bacterial second messenger cyclic‐di‐GMP. The genome of the human pathogen Pseudomonas aeruginosa PAO1 encodes two proteins (PA4108, PA4781) with an HD‐GYP domain and a third protein, PA2572, which contains a domain with variant key residues (YN‐GYP). Here we have investigated the role of these proteins in biofilm formation, virulence factor synthesis and vir...
Summary When grown as a biofilm in laboratory flow chambers Pseudomonas aeruginosa can develop mushroom‐shaped multicellular structures consisting of distinct subpopulations in the cap and stalk portions. We have previously presented evidence that formation of the cap portion of the mushroom‐shaped structures in P. aeruginosa biofilms occurs via bacterial migration and depends on type IV pili ( Mol Microbiol 50: 61–68). In the...
Summary The biofilm lifestyle, where microbial cells are aggregated because of expression of cell‐to‐cell interconnecting compounds, is believed to be of paramount importance to microbes in the environment. Because microbes must be able to alternate between sessile and planktonic states, it is anticipated that they must be able to regulate their ability to form biofilm and to dissolve biofilm. We present an investigation of a...
Role of commensal relationships on the spatial structure of a surface‐attached microbial consortiumNARA Subscribed
A flow cell‐grown model consortium consisting of two organisms, Burkholderia sp. LB400 and Pseudomonas sp. B13(FR1), was studied. These bacteria have the potential to interact metabolically because Pseudomonas sp. B13(FR1) can metabolize chlorobenzoate produced by Burkholderia sp. LB400 when grown on chlorobiphenyl. The expected metabolic interactions in the consortium were demonstrated by high performance liquid chromatograph...
Inhibition of Escherichia coli precursor‐16S rRNA processing by mouse intestinal contentsNARA Subscribed
The correlation between ribosome content and growth rate found in many bacterial species has proved useful for estimating the growth activity of individual cells by quantitative in situ rRNA hybridization. However, in dynamic environments, the stability of mature ribosomal RNA causes problems in using cellular rRNA contents for direct monitoring of bacterial growth activity in situ . In a recent paper, Cangelosi and Brabant su...
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