The Tat system allows the translocation of folded and often cofactor-containing proteins across biological membranes. Here, we show by an interspecies transfer of a complete Tat translocon that Tat systems are largely, but not fully, interchangeable even between different classes of proteobacteria. The Tat apparatus from the alpha-proteobacterium Rhodobacter capsulatus was transferred to a Tat-deficient Escherichia coli strain, which is a gamma-proteobacterium. Similar to that of E. coli, the R. capsulatus Tat system consists of three components, rc-TatA, rc-TatB, and rc-TatC. A fourth gene (rc-tatF) is present in the rc-tatABCF operon which has no apparent relevance for translocation. The translational starts of rc-tatC and rc-tatF overlap in four nucleotides (ATGA) with the preceding tat genes, pointing to efficient translational coupling of rc-tatB, rc-tatC, and rc-tatF. We show by a variety of physiological and biochemical assays that the R. capsulatus Tat system functionally targets the E. coli Tat substrates TorA, AmiA, AmiC, and formate dehydrogenase. Even a Tat substrate from a third organism is accepted, demonstrating that usually Tat systems and Tat substrates from different proteobacteria are compatible with each other. Only one exceptional Tat substrate of E. coli, a membrane-anchored dimethyl sulfoxide (DMSO) reductase, was not targeted by the R. capsulatus Tat system, resulting in a DMSO respiration deficiency. Although the general features of Tat substrates and translocons are similar between species, the data indicate that details in the targeting pathways can vary considerably.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1636324 | PMC |
http://dx.doi.org/10.1128/JB.01139-06 | DOI Listing |
Sci Adv
January 2025
Department of Bioengineering, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Having been predominantly observed in rigid metal and metal alloys since 1865, the magnetoelastic effect was recently experimentally discovered in a soft matter system and used as a new working mechanism for energy and health care applications. Here, a theoretical framework is presented and proven to be universally accurate and robust in interpreting the giant magnetoelastic effect across soft systems subjected to various deformation modes, micromagnet concentrations, magnetization profiles, and geometric structures. The theory uncovers substantial, unique magnetoelastic phenomena in soft systems, including the magnetic pole reversal under localized compression.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.
We report the precise measurements of the cross section of e^{+}e^{-}→hadrons at center-of-mass energies from 3.645 to 3.871 GeV.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Department of Neurodegenerative Diseases and Geriatric Psychiatry, University of Bonn Medical Center, Bonn, Germany.
Background: The identification of cognitively unimpaired individuals at risk of short-term cognitive decline is a critical task for Alzheimer´s disease (AD) research. Cognitively normal individuals with amyloid and/or tau pathology have a high risk for short-term cognitive decline. However, not all of these individuals show clinical progression.
View Article and Find Full Text PDFJ Thromb Haemost
December 2024
Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
Background: Therapeutic plasma exchange (TPE) is the primary intervention for treating symptomatic hyperviscosity from hypergammaglobulinemia, yet its efficacy for treating hyperviscosity related to hyperfibrinogenemia is unclear.
Objective: Define the safety and efficacy of TPE for critically ill COVID-19 patients with elevated blood viscosity from hyperfibrinogenemia.
Method: A prospective, randomized controlled trial in critically ill COVID-19 patients at a single US healthcare system.
Environ Technol
December 2024
Institute of Applied Technology and Sustainable Development, Nguyen Tat Thanh University, Ho Chi Minh City, Vietnam.
This study introduces a novel Revolving Algae Biofilm reactor for synthetic wastewater treatment, examining the influence of various biomass retention times (BRTs) on nutrient removal performance. The study reveals complex interactions between microalgae and bacteria, emphasizing their symbiotic functions in oxygen provision, nutrient absorption, and floc creation. This research contributes to the advancement of sustainable wastewater treatment methods, showing promise for large-scale nutrient removal in industrial settings.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!