15 research outputs found
A marine bacterial enzymatic cascade degrades the algal polysaccharide ulvan
International audienc
Ethical Textile Consumption: Only a Question of Selflessness?
When it comes to purchase decisions for fair-trade clothing, there seems to be a gap between actions and words. Only few people buy fair trade despite stating moral concerns. Based on a survey of German consumers and the results of a behavioral economic game, the article presents strategies to minimize the gap identified between the willingness to purchase and the moral standards that many consumers set for themselves.
The data suggests several consumer types and provides a few promising starting points for strategies that are not based on selflessness but rather generate more tangible benefits for the individual consumer groups. At least three of five consumer types or two-thirds of the consumers may constitute possible target groups according to the findings
De grensoverschrijdende arbeidsmarkt voor en gedurende de Covid-19 crisis: analyse van de belangrijkste problemen in 2020
Reaching out in anticipation: bacterial membrane extensions represent a permanent investment in polysaccharide sensing and utilization
Summary
Outer membrane extensions are common in many marine bacteria. However, the function of these surface enlargements or extracellular compartments is poorly understood. Using a combined approach of microscopy and subproteome analyses, we therefore examined Pseudoalteromonas distincta ANT/505, an Antarctic polysaccharide degrading gammaâproteobacterium. P. distincta produced outer membrane vesicles (MV) and vesicle chains (VC) on polysaccharide and nonâpolysaccharide carbon sources during the exponential and stationary growth phase. Surface structures of carbohydrateâgrown cells were equipped with increased levels of highly substrateâspecific proteins. At the same time, proteins encoded in all other polysaccharide degradationârelated genomic regions were also detected in MV and VC samples under all growth conditions, indicating a basal expression. In addition, two alkaline phosphatases were highly abundant under nonâlimiting phosphate conditions. Surface structures may thus allow rapid sensing and fast responses in nutritionally deprived environments. It may also facilitate efficient carbohydrate processing and reduce loss of substrates and enzymes by diffusion as important adaptions to the aquatic ecosystem
Reaching out in anticipation: bacterial membrane extensions represent a permanent investment in polysaccharide sensing and utilization
Summary
Outer membrane extensions are common in many marine bacteria. However, the function of these surface enlargements or extracellular compartments is poorly understood. Using a combined approach of microscopy and subproteome analyses, we therefore examined Pseudoalteromonas distincta ANT/505, an Antarctic polysaccharide degrading gammaâproteobacterium. P. distincta produced outer membrane vesicles (MV) and vesicle chains (VC) on polysaccharide and nonâpolysaccharide carbon sources during the exponential and stationary growth phase. Surface structures of carbohydrateâgrown cells were equipped with increased levels of highly substrateâspecific proteins. At the same time, proteins encoded in all other polysaccharide degradationârelated genomic regions were also detected in MV and VC samples under all growth conditions, indicating a basal expression. In addition, two alkaline phosphatases were highly abundant under nonâlimiting phosphate conditions. Surface structures may thus allow rapid sensing and fast responses in nutritionally deprived environments. It may also facilitate efficient carbohydrate processing and reduce loss of substrates and enzymes by diffusion as important adaptions to the aquatic ecosystem
Branching ratio of the C2H2 + O reaction at 290 K from kinetic modelling of relative methylene concentration versus time profiles in C2H2/O/H systems
Synergy between Cell Surface Glycosidases and Glycan-Binding Proteins Dictates the Utilization of Specific Beta(1,3)-Glucans by Human Gut Bacteroides
Adaptive mechanisms that provide competitive advantages to marine bacteroidetes during microalgal blooms
Polysaccharide degradation by heterotrophic microbes is a key process within Earth's carbon cycle. Here, we use environmental proteomics and metagenomics in combination with cultivation experiments and biochemical characterizations to investigate the molecular details of in situ polysaccharide degradation mechanisms during microalgal blooms. For this, we use laminarin as a model polysaccharide. Laminarin is a ubiquitous marine storage polymer of marine microalgae and is particularly abundant during phytoplankton blooms. In this study, we show that highly specialized bacterial strains of the Bacteroidetes phylum repeatedly reached high abundances during North Sea algal blooms and dominated laminarin turnover. These genomically streamlined bacteria of the genus Formosa have an expanded set of laminarin hydrolases and transporters that belonged to the most abundant proteins in the environmental samples. In vitro experiments with cultured isolates allowed us to determine the functions of in situ expressed key enzymes and to confirm their role in laminarin utilization. It is shown that laminarin consumption of Formosa spp. is paralleled by enhanced uptake of diatom-derived peptides. This study reveals that genome reduction, enzyme fusions, transporters, and enzyme expansion as well as a tight coupling of carbon and nitrogen metabolism provide the tools, which make Formosa spp. so competitive during microalgal blooms