transport activity
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2022 ◽  
pp. 44-62
Author(s):  
José Cabezas ◽  
José Manuel Naranjo ◽  
Francisco Jesús Moral ◽  
Patricia Bratos

The development carried out in the last decades is degrading the ecosystems, damaging the existing biodiversity. One of the elements that is having the most impact on the deterioration of natural areas is the construction of transport infrastructures, among which are high-speed routes. These linear infrastructures are contributing to the deterioration of biodiversity enclaves, which contribute to providing highly relevant ecosystem services. Among these deteriorations are the processes of fragmentation and alteration of the landscape. This chapter analyses a situation that occurs in Spanish territory related to high-speed railways. This transport system began in Spain on the occasion of the Universal Exhibition of Seville 1992. By this transport activity, the changes suffered in the landscape are calculated and analysed through Corine land cover data since its inception until the last report of 2018.


2022 ◽  
Vol 10 (1) ◽  
Author(s):  
Kazutaka Ushio ◽  
Erika Watanabe ◽  
Takehiro Kamiya ◽  
Ayumi Nagashima ◽  
Tadaomi Furuta ◽  
...  

2021 ◽  
Vol 22 (24) ◽  
pp. 13565
Author(s):  
Kristin Oepen ◽  
Hüseyin Özbek ◽  
Anja Schüffler ◽  
Johannes C. Liermann ◽  
Eckhard Thines ◽  
...  

ATP-binding cassette (ABC) transporters are conserved in all kingdoms of life, where they transport substrates against a concentration gradient across membranes. Some ABC transporters are known to cause multidrug resistances in humans and are able to transport chemotherapeutics across cellular membranes. Similarly, BmrA, the ABC transporter of Bacillus subtilis, is involved in excretion of certain antibiotics out of bacterial cells. Screening of extract libraries isolated from fungi revealed that the C14 fatty acid myristic acid has an inhibitory effect on the BmrA ATPase as well as the transport activity. Thus, a natural membrane constituent inhibits the BmrA activity, a finding with physiological consequences as to the activity and regulation of ABC transporter activities in biological membranes.


Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3554
Author(s):  
Sana Latif ◽  
Young-Sook Kang

L-Arginine, a semi-essential amino acid, was shown to delay dysfunction of motor neurons and to prolong the lifespan, upon analysis of transgenic mouse models of amyotrophic lateral sclerosis (ALS). We investigated the transport function of arginine and neuronal nitric oxide synthase (nNOS) expression after pretreatment with L-arginine in NSC-34 hSOD1WT (wild-type, WT) and hSOD1G93A (mutant-type, MT) cell lines. [3H]L-Arginine uptake was concentration-dependent, voltage-sensitive, and sodium-independent in both cell lines. Among the cationic amino acid transporters family, including system y+, b0,+, B0,+, and y+L, system y+ is mainly involved in [3H]L-arginine transport in ALS cell lines. System b0,+ accounted for 23% of the transport in both cell lines. System B0,+ was found only in MT, and whereas, system y+L was found only in WT. Lysine competitively inhibited [3H]L-arginine uptake in both cell lines. The nNOS mRNA expression was significantly lower in MT than in WT. Pretreatment with arginine elevated nNOS mRNA levels in MT. Oxidizing stressor, H2O2, significantly decreased their uptake; however, pretreatment with arginine restored the transport activity in both cell lines. In conclusion, arginine transport is associated with system y+, and neuroprotection by L-arginine may provide an edge as a possible therapeutic target in the treatment of ALS.


Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2518
Author(s):  
Jiangnan Yu ◽  
Ying Liu ◽  
Bowen Huang ◽  
Chen Li ◽  
Dandan Wang ◽  
...  

The interaction between viral membrane associate proteins and host cellular surface molecules should facilitate the attachment and entry of OsHV-1 into host cells. Thus, blocking the putative membrane proteins ORF25 and ORF72 of OsHV-1 with antibodies that have previously been reported to subdue OsHV-1 replication in host cells, especially ORF25. In this study, prey proteins in host hemocytes were screened by pull-down assay with recombinant baits ORF25 and ORF72, respectively. Gene Ontology (GO) analysis of these prey proteins revealed that most of them were mainly associated with binding, structural molecule activity and transport activity in the molecular function category. The protein–protein interaction (PPI) network of the prey proteins was constructed by STRING and clustered via K-means. For both ORF25 and ORF72, three clusters of these prey proteins were distinguished that were mainly associated with cytoskeleton assembly, energy metabolism and nucleic acid processing. ORF25 tended to function in synergy with actins, while ORF72 functioned mainly with tubulins. The above results suggest that these two putative membrane proteins, ORF25 and ORF72, might serve a role in the transport of viral particles with the aid of a cytoskeleton inside cells.


Nano Letters ◽  
2021 ◽  
Author(s):  
Tengfei Yan ◽  
Shengda Liu ◽  
Jiayun Xu ◽  
Hongcheng Sun ◽  
Shuangjiang Yu ◽  
...  

Author(s):  
Leszek MINDUR ◽  
Maciej MINDUR

The excessive increase in transport intensity is one of the negative impacts on the economy. The costs borne due to transport activities are indirectly expressed by the volume of carriages (in tons) and by the scope of transport activity (in ton-kilometers). The result of social and economic activities are global product values and national incomes. This article shows the research on transport activity expressed through transport activity (in ton-kilometers) for all means of transport in total, the results of social and economic activities expressed using the gross domestic product, as well as shaping transport intensity of national economies in selected European countries. The analysis of the course of the exponential function curves, as well as polynomial curves has been carried out, and conclusions have been formulated on their bases.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Dawei Guo ◽  
Himansha Singh ◽  
Atsushi Shimoyama ◽  
Charlotte Guffick ◽  
Yakun Tang ◽  
...  

AbstractThe ABC multidrug exporter MsbA mediates the translocation of lipopolysaccharides and phospholipids across the plasma membrane in Gram-negative bacteria. Although MsbA is structurally well characterised, the energetic requirements of lipid transport remain unknown. Here, we report that, similar to the transport of small-molecule antibiotics and cytotoxic agents, the flopping of physiologically relevant long-acyl-chain 1,2-dioleoyl (C18)-phosphatidylethanolamine in proteoliposomes requires the simultaneous input of ATP binding and hydrolysis and the chemical proton gradient as sources of metabolic energy. In contrast, the flopping of the large hexa-acylated (C12-C14) Lipid-A anchor of lipopolysaccharides is only ATP dependent. This study demonstrates that the energetics of lipid transport by MsbA is lipid dependent. As our mutational analyses indicate lipid and drug transport via the central binding chamber in MsbA, the lipid availability in the membrane can affect the drug transport activity and vice versa.


2021 ◽  
Vol 22 (23) ◽  
pp. 12998
Author(s):  
Jin-Yan Zhou ◽  
Dong-Li Hao ◽  
Guang-Zhe Yang

Cytosolic pH homeostasis is a precondition for the normal growth and stress responses in plants, and H+ flux across the plasma membrane is essential for cytoplasmic pH control. Hence, this review focuses on seven types of proteins that possess direct H+ transport activity, namely, H+-ATPase, NHX, CHX, AMT, NRT, PHT, and KT/HAK/KUP, to summarize their plasma-membrane-located family members, the effect of corresponding gene knockout and/or overexpression on cytosolic pH, the H+ transport pathway, and their functional regulation by the extracellular/cytosolic pH. In general, H+-ATPases mediate H+ extrusion, whereas most members of other six proteins mediate H+ influx, thus contributing to cytosolic pH homeostasis by directly modulating H+ flux across the plasma membrane. The fact that some AMTs/NRTs mediate H+-coupled substrate influx, whereas other intra-family members facilitate H+-uncoupled substrate transport, demonstrates that not all plasma membrane transporters possess H+-coupled substrate transport mechanisms, and using the transport mechanism of a protein to represent the case of the entire family is not suitable. The transport activity of these proteins is regulated by extracellular and/or cytosolic pH, with different structural bases for H+ transfer among these seven types of proteins. Notably, intra-family members possess distinct pH regulatory characterization and underlying residues for H+ transfer. This review is anticipated to facilitate the understanding of the molecular basis for cytosolic pH homeostasis. Despite this progress, the strategy of their cooperation for cytosolic pH homeostasis needs further investigation.


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