Bacteriophages targeting Enterococcus faecalis enhance the therapeutic efficacy of levodopa in an MPTP-induced Parkinson's disease mouse model with E. faecalis gut colonization.

Despite the intensive research on gut microbiome-associated diseases over the past 20 years, pharmacological methods for effectively eliminating pathobionts remain unsatisfactory. This study investigated the therapeutic potential of bacteriophages against Enterococcus faecalis, in which bacterial tyrosine decarboxylase (TDC) converts orally administered levodopa (L-DOPA) to dopamine, in an MPTP mouse model of Parkinson's disease (PD). E.

Proton-pumping photoreceptor controls expression of ABC transporter by regulating transcription factor through light.

Light is a significant factor for living organisms with photosystems, like microbial rhodopsin-a retinal protein that functions as an ion pump, channel, and sensory transduction. Gloeobacter violaceus PCC7421, has a proton-pumping rhodopsin gene, the Gloeobacter rhodopsin (GR). The helix-turn-helix family of transcriptional regulators has various motifs, and they regulate gene expression in the presence of various metal ions.

Heliorhodopsin-mediated light-modulation of ABC transporter.

Heliorhodopsins (HeRs) have been hypothesized to have widespread functions. Recently, the functions for few HeRs have been revealed; however, the hypothetical functions remain largely unknown. Herein, we investigate light-modulation of heterodimeric multidrug resistance ATP-binding cassette transporters (OmrDE) mediated by Omithinimicrobium cerasi HeR.

Impact of protein-chromophore interaction on the retinal excited state and photocycle of rhodopsin: role of conserved tryptophan residues.

The function of microbial as well as mammalian retinal proteins ( rhodopsins) is associated with a photocycle initiated by light excitation of the retinal chromophore of the protein, covalently bound through a protonated Schiff base linkage. Although electrostatics controls chemical reactions of many organic molecules, attempt to understand its role in controlling excited state reactivity of rhodopsins and, thereby, their photocycle is scarce. Here, we investigate the effect of highly conserved tryptophan residues, between which the all- retinal chromophore of the protein is sandwiched in microbial rhodopsins, on the charge distribution along the retinal excited state, quantum yield and nature of the light-induced photocycle and absorption properties of rhodopsin (GR).

Heliorhodopsin Helps Photolyase to Enhance the DNA Repair Capacity.

Light quality is a significant factor for living organisms that have photosensory systems, such as rhodopsin, a seven alpha-helical transmembrane protein with the retinal chromophore. Here, we report, for the first time, the function of new rhodopsin, which is an inverted 7-transmembrane protein, isolated from Trichococcus flocculiformis heliorhodopsin (TfHeR) works as a regulatory helper rhodopsin that binds with class 2 cyclobutane pyrimidine dimer (CPDII) photolyase to broaden the spectrum and upregulate DNA repair activity. We have confirmed their interaction through isothermal titration calorimetry (dissociation constant of 21.

Heliorhodopsin binds and regulates glutamine synthetase activity.

Photoreceptors are light-sensitive proteins found in various organisms that respond to light and relay signals into the cells. Heliorhodopsin, a retinal-binding membrane protein, has been recently discovered, however its function remains unknown. Herein, we investigated the relationship between Actinobacteria bacterium IMCC26103 heliorhodopsin (AbHeR) and an adjacent glutamine synthetase (AbGS) in the same operon.

Fabrication of a Tailored, Hybrid Extracellular Matrix Composite.

The extracellular matrix (ECM) is a network of connective fibers that supports cells living in their surroundings. Native ECM, generated by the secretory products of each tissue's resident cells, has a unique architecture with different protein composition depending on the tissue. Therefore, it is very difficult to artificially design in vivo architecture in tissue engineering.

Carotenoid binding in Gloeobacteria rhodopsin provides insights into divergent evolution of xanthorhodopsin types.

The position of carotenoid in xanthorhodopsin has been elucidated. However, a challenging expression of this opsin and a complex biosynthesis carotenoid in the laboratory hold back the insightful study of this rhodopsin. Here, we demonstrated co-expression of the xanthorhodopsin type isolated from Gloeobacter violaceus PCC 7421-Gloeobacter rhodopsin (GR) with a biosynthesized keto-carotenoid (canthaxanthin) targeting the carotenoid binding site.

Mutational analyses identify a single amino acid critical for colour tuning in proteorhodopsins.

Microbial rhodopsins are light-activated proteins that contain seven transmembrane alpha-helices. Spectral tuning in microbial rhodopsins is a useful optogenetic tool. In this study, we report a new site that controls spectral tuning.

Discovery of a new light-driven Li/Na-pumping rhodopsin with DTG motif.

Microbial pumping rhodopsin is a seven-transmembrane retinal binding protein, which is light-driven ion pump with a functional key motif. Ion-pumping with the key motif and charged amino acids in the rhodopsin is biochemically important. The rhodopsins with DTG motif have been discovered in various eubacteria, and they function as H pump.

Discovery of a microbial rhodopsin that is the most stable in extreme environments.

Microbial rhodopsin is a retinal protein that functions as an ion pump, channel, and sensory transducer, as well as a light sensor, as in biosensors and biochips. Tara76 rhodopsin is a typical proton-pumping rhodopsin that exhibits strong stability against extreme pH, detergent, temperature, salt stress, and dehydration stress and even under dual and triple conditions. Tara76 rhodopsin has a thermal stability approximately 20 times higher than that of thermal rhodopsin at 80°C and is even stable at 85°C.

The role of carotenoids in proton-pumping rhodopsin as a primitive solar energy conversion system.

Rhodopsin and carotenoids are two molecules that certain bacteria use to absorb and utilize light. Type I rhodopsin, the simplest active proton transporter, converts light energy into an electrochemical potential. Light produces a proton gradient, which is known as the proton motive force across the cell membrane.

Assembly of Natively Synthesized Dual Chromophores Into Functional Actinorhodopsin.

Microbial rhodopsin is a simple solar energy-capturing molecule compared to the complex photosynthesis apparatus. Light-driven proton pumping across the cell membrane is a crucial mechanism underlying microbial energy production. is one of the highly abundant bacterial phyla in freshwater habitats, and members of this lineage are considered to boost heterotrophic growth phototrophy, as indicated by the presence of actino-opsin (ActR) genes in their genome.

The Use of a Chimeric Rhodopsin Vector for the Detection of New Proteorhodopsins Based on Color.

Student microbial ecology laboratory courses are often conducted as condensed courses in which theory and wet lab work are combined in a very intensive short time period. In last decades, the study of marine microbial ecology is increasingly reliant on molecular-based methods, and as a result many of the research projects conducted in such courses require sequencing that is often not available on site and may take more time than a typical course allows. In this work, we describe a protocol combining molecular and functional methods for analyzing proteorhodopsins (PRs), with visible results in only 4-5 days that do not rely on sequencing.