Biology subjects

Foerster, B.

Publications and source records attributed to Foerster, B..

4 recordsLinked to original sources

bioRxiv2025

Effects of a Sequential Application of Plant Protection Products on Soil Microbes and Free-Living Nematodes in a Field Experiment

During crop growth cycle, often several different plant protection products (PPPs) are applied, in combination or sequentially. Such sequential applications result in unintentional mixtures of residues that may affect ecosystem services supported by non-target organisms such as soil microbes and nematodes. This scenario of sequential PPP application is frequent in agricultural practice but rarely addressed experimentally at field scale with regard to environmental impacts. The objective of this study was to evaluate the effect of individual and sequential application of three PPPs (the herbicide clopyralid, the insecticide zeta-cypermethrin, and the fungicide pyraclostrobin) on soil microbial communities, and on the abundance of free-living nematode. Single applications (at 1x or 10x the agronomical dose) were made to triplicated field plots with each one of the PPPs or all three PPPs in sequence, with untreated plots serving as controls. Plots were sampled prior to each application, and 7 and 28 days thereafter. The fungal communitys composition and abundance were found to be more susceptible than the bacterial community to PPP applications, while the bacterial was mainly driven by the in-field heterogeneity of soil properties. Transient effects of PPP applications were detected on nematode abundance. Higher tier ecotoxicological studies offer greater ecological relevance compared to the standard laboratory tests but are challenged by environmental variations that should be accounted for when evaluating the ecotoxicity of pesticides on soil organisms.

ecology↗

bioRxiv2023

Effect of a topically applied gel containing antibodies from bovine milk on the relative abundance of Staphylococci in the canine skin microbiome

Canine pyoderma is characterised by a predominant colonisation of the skin with Staphylococcus pseudintermedius and inflammatory symptoms associated with it. Immunoglobulins isolated from cow ss milk are neutralizing virulence factors and toxins of S. pseudintermedius. In a pilot study with four dogs with pyoderma we were able to show that the application of immunoglobulin gel leads to a decrease in the staphylococcal population and an increase in the diversity of the skin microbiome. Due to the limited number of animals, the measurable effect is not statistically significant. Therefore, we are planning a follow-up study that includes more animals.

microbiology↗

bioRxiv2021

Regulatory adenylnucleotide-mediated binding of the PII-like protein SbtB to the cyanobacterial bicarbonate transporter SbtA is controlled by the cellular energy state

Cyanobacteria have evolved a remarkably powerful CO2 concentrating mechanism (CCM), enabling high photosynthetic rates in environments with limited inorganic carbon (Ci). Therefore, this CCM is a promising system for integration into higher plant chloroplasts to boost photosynthetic efficiency and yield. The CCM depends on active Ci uptake, facilitated by bicarbonate transporters and CO2 pumps, to elevate CO2 concentration around the active sites of the primary CO2 fixing enzyme, Rubisco, which is encapsulated in cytoplasmic micro-compartments (carboxysomes). The essential CCM proteins have been identified, but the molecular signals and regulators that coordinate function in response to light, Ci availability and other environmental cues are largely unknown. Here, we provide evidence, based on a novel in vitro binding system, for a role of the PII-like SbtB protein in regulating Ci uptake by the bicarbonate transporter, SbtA, in response to the cellular adenylate energy charge (AEC) through dynamic protein-protein interaction. Binding of the SbtA and SbtB proteins from two phylogenetically distant species, Cyanobium sp. PCC7001 and Synechococcus elongatus PCC7942, was inhibited by high ATP, and promoted by low [ATP]:[ADP or AMP] ratios in vitro, consistent with a sensory response to the AEC mediated through adenylnucleotide ligand-specific conformation changes in SbtB. In vivo, cell cultures of S. elongatus showed up to 70% SbtB-dependent down-regulation of SbtA bicarbonate uptake activity specifically in the light activation phase during transitions from dark to low light when low cellular AEC is expected to limit metabolic activity. This suggests SbtB may function as a curfew protein during prolonged low cellular AEC and photosynthetically unfavourable conditions to prevent energetically futile and physiologically disadvantageous activation of SbtA.

plant biology↗

bioRxiv2018

Michigan Neural Distinctiveness (MiND) project: Investigating the scope, causes, and consequences of age-related neural dedifferentiation

BackgroundAging is often associated with behavioral impairments, but some people age more gracefully than others. Why? One factor that may play a role is individual differences in the distinctiveness of neural representations. Previous research has found that neural activation patterns in visual cortex in response to different visual stimuli are often more similar (i.e., less distinctive) in older vs. young participants, a phenomenon referred to as age-related neural dedifferentiation. Furthermore, older people whose neural representations are less distinctive tend to perform worse on a wide range of behavioral tasks. The Michigan Neural Distinctiveness (MiND) project aims to investigate the scope of neural dedifferentiation (e.g., does it also occur in auditory, motor, and somatosensory cortex?), one potential cause (age-related reductions in the inhibitory neurotransmitter gamma-aminobutyric acid (GABA)), and the behavioral consequences of neural dedifferentiation. This protocol paper describes the study rationale and methods being used in complete detail, but not the results (data collection is currently underway).\n\nMethods/DesignThe MiND project consists of two studies: the main study and a drug study. In the main study, we are recruiting 60 young and 100 older adults to perform behavioral tasks that measure sensory and cognitive function. They also participate in functional MRI (fMRI), MR spectroscopy (MRS), and diffusion weighted imaging (DWI) sessions, providing data on neural distinctiveness and GABA concentrations. In the drug study, we are recruiting 25 young and 25 older adults to compare neural distinctiveness, measured with fMRI, after participants take (1) a benzodiazepine (lorazepam) that should increase GABA activity or (2) a placebo.\n\nDiscussionBy collecting multimodal imaging measures (fMRI, MRS, DWI) along with extensive behavioral measures from the same subjects, we are linking individual differences in neurochemistry, neural representation, and behavioral performance, rather than focusing solely on group differences between young and old participants. Our findings have the potential to inform new interventions for age-related declines.

neuroscience↗