Transcriptional activity differentiates families of Marine Group II Euryarchaeota in the coastal ocean

AbstractMarine Group II Euryarchaeota (Candidatus Poseidoniales), abundant but yet-uncultivated members of marine microbial communities, are thought to be (photo)heterotrophs that metabolize dissolved organic matter (DOM), such as lipids and peptides. However, little is known about their transcriptional activity. We mapped reads from a metatranscriptomic time series collected at Sapelo Island (GA, USA) to metagenome-assembled genomes to determine the diversity of transcriptionally active Ca. Poseidoniales. Summer metatranscriptomes had the highest abundance of Ca. Poseidoniales transcripts, mostly from the O1 and O3 genera within Ca. Thalassarchaeaceae (MGIIb). In contrast, transcripts from fall and winter samples were predominantly from Ca. Poseidoniaceae (MGIIa). Genes encoding proteorhodopsin, membrane-bound pyrophosphatase, peptidase/proteases, and part of the ß-oxidation pathway were highly transcribed across abundant genera. Highly transcribed genes specific to Ca. Thalassarchaeaceae included xanthine/uracil permease and receptors for amino acid transporters. Enrichment of Ca. Thalassarchaeaceae transcript reads related to protein/peptide, nucleic acid, and amino acid transport and metabolism, as well as transcript depletion during dark incubations, provided further evidence of heterotrophic metabolism. Quantitative PCR analysis of South Atlantic Bight samples indicated consistently abundant Ca. Poseidoniales in nearshore and inshore waters. Together, our data suggest that Ca. Thalassarchaeaceae are important photoheterotrophs potentially linking DOM and nitrogen cycling in coastal waters.

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Transcriptional activity differentiates families of Marine Group II Euryarchaeota in the coastal ocean

10.1101/2020.09.16.299958 ◽

2020 ◽

Author(s):

Julian Damashek ◽

Aimee Oyinlade Okotie-Oyekan ◽

Scott Michael Gifford ◽

Alexey Vorobev ◽

Mary Ann Moran ◽

...

Keyword(s):

Amino Acid ◽

Transcriptional Activity ◽

Pcr Analysis ◽

South Atlantic Bight ◽

Amino Acid Transporters ◽

Genes Encoding ◽

Heterotrophic Metabolism ◽

Inshore Waters ◽

Group Ii ◽

Marine Microbial Communities

ABSTRACTMarine Group II Euryarchaeota (Candidatus Poseidoniales), abundant but yet-uncultivated members of marine microbial communities, are thought to be (photo)heterotrophs that metabolize dissolved organic matter (DOM) such as lipids and peptides. However, little is known about their transcriptional activity. We mapped reads from a metatranscriptomic time series collected at Sapelo Island (GA, USA) to metagenome-assembled genomes to determine the diversity of transcriptionally-active Ca. Poseidoniales. Summer metatranscriptomes had the highest abundance of Ca. Poseidoniales transcripts, mostly from the O1 and O3 genera within Ca. Thalassarchaeaceae (MGIIb). In contrast, transcripts from fall and winter samples were predominantly from Ca. Poseidoniaceae (MGIIa). Genes encoding proteorhodopsin, membrane-bound pyrophosphatase, peptidase/proteases, and part of the β-oxidation pathway were highly transcribed across abundant genera. Highly transcribed genes specific to Ca. Thalassarchaeaceae included xanthine/uracil permease and receptors for amino acid transporters. Enrichment of Ca. Thalassarchaeaceae transcript reads related to protein/peptide, nucleic acid, and amino acid transport and metabolism, as well as transcript depletion during dark incubations, provided further evidence of heterotrophic metabolism. Quantitative PCR analysis of South Atlantic Bight samples indicated consistently abundant Ca. Poseidoniales in nearshore and inshore waters. Together, our data suggest Ca. Thalassarchaeaceae are important photoheterotrophs potentially linking DOM and nitrogen cycling in coastal waters.

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Expression of selected genes encoding mechanistic pathways, nutrient and amino acid transporters in jejunum and ileum of broiler chickens fed a reduced protein diet supplemented with arginine, glutamine and glycine under stress stimulated by dexamethasone

Journal of Animal Physiology and Animal Nutrition ◽

10.1111/jpn.13416 ◽

2020 ◽

Author(s):

Reza Barekatain ◽

Peter V. Chrystal ◽

Saad Gilani ◽

Clive J. McLaughlan

Keyword(s):

Amino Acid ◽

Broiler Chickens ◽

Protein Diet ◽

Amino Acid Transporters ◽

Genes Encoding

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Biochemical aspects of assimilate transfers along the phloem path: N-solutes in lupins

Functional Plant Biology ◽

10.1071/pp99129 ◽

2000 ◽

Vol 27 (6) ◽

pp. 531 ◽

Cited By ~ 6

Author(s):

Craig Atkins

Keyword(s):

Amino Acid ◽

Root System ◽

Seed Coat ◽

Significant Feature ◽

Amino Acid Transporters ◽

Direct Transfer ◽

Selective Transfer ◽

Long Distance ◽

Shoot Apices ◽

Genes Encoding

Lupins (Lupinus angustifolius L., L. albus L.) are prolific ‘phloem bleeders’, allowing collection of exu-dates en route to or at phloem-fed sinks such as shoot apices, developing fruits and the root system, as well as at or exiting the sources of phloem-borne solutes, leaves, petioles and stems. Consequently, it has been possible to quan-tify the relative contributions of xylem and phloem solutes to the nutrition of each developing organ of a lupin plant. Studies that identify the sites and, especially for solutes containing N, the nature of transfers between the two long distance translocation channels are reviewed. These transfers are solute-specific and can be accounted for largely by transfer of asparagine. In leaves, direct transfer of asparagine from xylem to phloem in minor veins, such that metabolism is precluded, is the most significant feature of N redistribution in the shoot. Current research is aimed at identifying and isolating genes encoding amino acid transporters expressed in strategically placed cells (possibly transfer cells) at nodes, at the inner epidermis of the seed coat and the epidermis of the developing cotyledons. Special emphasis is placed on transporters for selective transfer of asparagine.

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Identification of genetic and phenotypic differences associated with prevalent and non-prevalent Salmonella Enteritidis phage types: analysis of variation in amino acid transport

Microbiology ◽

10.1099/mic.0.029405-0 ◽

2009 ◽

Vol 155 (10) ◽

pp. 3200-3213 ◽

Cited By ~ 20

Author(s):

Zhensheng Pan ◽

Ben Carter ◽

Javier Núñez-García ◽

Manal AbuOun ◽

María Fookes ◽

...

Keyword(s):

Amino Acid ◽

Salmonella Enteritidis ◽

Selective Advantage ◽

Comparative Genomic ◽

Amino Acid Transporters ◽

Phenotypic Differences ◽

Phage Types ◽

Genes Encoding ◽

Genetic Level ◽

Analysis Of Variation

In this study, differences at the genetic level of 37 Salmonella Enteritidis strains from five phage types (PTs) were compared using comparative genomic hybridization (CGH) to assess differences between PTs. There were approximately 400 genes that differentiated prevalent (4, 6, 8 and 13a) and sporadic (11) PTs, of which 35 were unique to prevalent PTs, including six plasmid-borne genes, pefA, B, C, D, srgC and rck, and four chromosomal genes encoding putative amino acid transporters. Phenotype array studies also demonstrated that strains from prevalent PTs were less susceptible to urea stress and utilized l-histidine, l-glutamine, l-proline, l-aspartic acid, gly-asn and gly-gln more efficiently than PT11 strains. Complementation of a PT11 strain with the transporter genes from PT4 resulted in a significant increase in utilization of the amino acids and reduced susceptibility to urea stress. In epithelial cell association assays, PT11 strains were less invasive than other prevalent PTs. Most strains from prevalent PTs were better biofilm formers at 37 °C than at 28 °C, whilst the converse was true for PT11 strains. Collectively, the results indicate that genetic and corresponding phenotypic differences exist between strains of the prevalent PTs 4, 6, 8 and 13a and non-prevalent PT11 strains that are likely to provide a selective advantage for strains from the former PTs and could help them to enter the food chain and cause salmonellosis.

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Amino Acid Transporters on the Guard of Cell Genome and Epigenome

Cancers ◽

10.3390/cancers13010125 ◽

2021 ◽

Vol 13 (1) ◽

pp. 125

Author(s):

Uğur Kahya ◽

Ayşe Sedef Köseer ◽

Anna Dubrovska

Keyword(s):

Amino Acid ◽

Cancer Metabolism ◽

Tumor Imaging ◽

Redox Homeostasis ◽

Amino Acid Uptake ◽

Metabolic Reprogramming ◽

Tumor Evolution ◽

Amino Acid Transporters ◽

Acid Uptake ◽

Growth And Survival

Tumorigenesis is driven by metabolic reprogramming. Oncogenic mutations and epigenetic alterations that cause metabolic rewiring may also upregulate the reactive oxygen species (ROS). Precise regulation of the intracellular ROS levels is critical for tumor cell growth and survival. High ROS production leads to the damage of vital macromolecules, such as DNA, proteins, and lipids, causing genomic instability and further tumor evolution. One of the hallmarks of cancer metabolism is deregulated amino acid uptake. In fast-growing tumors, amino acids are not only the source of energy and building intermediates but also critical regulators of redox homeostasis. Amino acid uptake regulates the intracellular glutathione (GSH) levels, endoplasmic reticulum stress, unfolded protein response signaling, mTOR-mediated antioxidant defense, and epigenetic adaptations of tumor cells to oxidative stress. This review summarizes the role of amino acid transporters as the defender of tumor antioxidant system and genome integrity and discusses them as promising therapeutic targets and tumor imaging tools.

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Pichia pastoris and the Recombinant Human Heterodimeric Amino Acid Transporter 4F2hc-LAT1: From Clone Selection to Pure Protein

Methods and Protocols ◽

10.3390/mps4030051 ◽

2021 ◽

Vol 4 (3) ◽

pp. 51

Author(s):

Satish Kantipudi ◽

Daniel Harder ◽

Sara Bonetti ◽

Dimitrios Fotiadis ◽

Jean-Marc Jeckelmann

Keyword(s):

Amino Acid ◽

Pichia Pastoris ◽

Protein Complexes ◽

Amino Acid Transporter ◽

Amino Acid Transporters ◽

Expression Host ◽

Amino Acids And Derivatives ◽

Heterodimeric Complex ◽

Acid Transporter ◽

And Function

Heterodimeric amino acid transporters (HATs) are protein complexes composed of two subunits, a heavy and a light subunit belonging to the solute carrier (SLC) families SLC3 and SLC7. HATs transport amino acids and derivatives thereof across the plasma membrane. The human HAT 4F2hc-LAT1 is composed of the type-II membrane N-glycoprotein 4F2hc (SLC3A2) and the L-type amino acid transporter LAT1 (SLC7A5). 4F2hc-LAT1 is medically relevant, and its dysfunction and overexpression are associated with autism and tumor progression. Here, we provide a general applicable protocol on how to screen for the best membrane transport protein-expressing clone in terms of protein amount and function using Pichia pastoris as expression host. Furthermore, we describe an overexpression and purification procedure for the production of the HAT 4F2hc-LAT1. The isolated heterodimeric complex is pure, correctly assembled, stable, binds the substrate L-leucine, and is thus properly folded. Therefore, this Pichia pastoris-derived recombinant human 4F2hc-LAT1 sample can be used for downstream biochemical and biophysical characterizations.

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Characterization of the third member of the MCAT family of cationic amino acid transporters. Identification of a domain that determines the transport properties of the MCAT proteins.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)36854-1 ◽

1993 ◽

Vol 268 (28) ◽

pp. 20796-20800

Author(s):

E.I. Closs ◽

C.R. Lyons ◽

C Kelly ◽

J.M. Cunningham

Keyword(s):

Amino Acid ◽

Transport Properties ◽

Amino Acid Transporters ◽

Cationic Amino Acid ◽

The Third

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LAT1 and ASCT2 Related microRNAs as Potential New Therapeutic Agents against Colorectal Cancer Progression

Biomedicines ◽

10.3390/biomedicines9020195 ◽

2021 ◽

Vol 9 (2) ◽

pp. 195

Author(s):

Francisca Dias ◽

Cristina Almeida ◽

Ana Luísa Teixeira ◽

Mariana Morais ◽

Rui Medeiros

Keyword(s):

Colorectal Cancer ◽

Amino Acid ◽

Cancer Progression ◽

Cell Metabolism ◽

Tumor Development ◽

Amino Acid Transporters ◽

Epigenetic Alterations ◽

Therapeutic Approaches ◽

Colorectal Cancer Progression ◽

Made In

The development and progression of colorectal cancer (CRC) have been associated with genetic and epigenetic alterations and more recently with changes in cell metabolism. Amino acid transporters are key players in tumor development, and it is described that tumor cells upregulate some AA transporters in order to support the increased amino acid (AA) intake to sustain the tumor additional needs for tumor growth and proliferation through the activation of several signaling pathways. LAT1 and ASCT2 are two AA transporters involved in the regulation of the mTOR pathway that has been reported as upregulated in CRC. Some attempts have been made in order to develop therapeutic approaches to target these AA transporters, however none have reached the clinical setting so far. MiRNA-based therapies have been gaining increasing attention from pharmaceutical companies and now several miRNA-based drugs are currently in clinical trials with promising results. In this review we combine a bioinformatic approach with a literature review in order to identify a miRNA profile with the potential to target both LAT1 and ASCT2 with potential to be used as a therapeutic approach against CRC.

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Roles of Si and SiNPs in Improving Thermotolerance of Wheat Photosynthetic Machinery via Upregulation of PsbH, PsbB and PsbD Genes Encoding PSII Core Proteins

Horticulturae ◽

10.3390/horticulturae7020016 ◽

2021 ◽

Vol 7 (2) ◽

pp. 16

Author(s):

Heba Hassan ◽

Aishah Alatawi ◽

Awatif Abdulmajeed ◽

Manal Emam ◽

Hemmat Khattab

Keyword(s):

Photosystem Ii ◽

Global Climate ◽

Soluble Sugars ◽

Triticum Aestivum L ◽

Pcr Analysis ◽

Silicon Dioxide Nanoparticles ◽

System Productivity ◽

Photosynthetic System ◽

Core Proteins ◽

Genes Encoding

Photosystem II is extremely susceptible to environmental alterations, particularly high temperatures. The maintenance of an efficient photosynthetic system under stress conditions is one of the main issues for plants to attain their required energy. Nowadays, searching for stress alleviators is the main goal for maintaining photosynthetic system productivity and, thereby, crop yield under global climate change. Potassium silicate (K2SiO3, 1.5 mM) and silicon dioxide nanoparticles (SiO2NPs, 1.66 mM) were used to mitigate the negative impacts of heat stress (45 °C, 5 h) on wheat (Triticum aestivum L.) cv. (Shandawelly) seedlings. The results showed that K2SiO3 and SiO2NPs diminished leaf rolling symptoms and electrolyte leakage (EL) of heat-stressed wheat leaves. Furthermore, the maximum quantum yield of photosystem II (Fv/Fm) and the performance index (PIabs), as well as the photosynthetic pigments and organic solutes including soluble sugars, sucrose, and proline accumulation, were increased in K2SiO3 and SiO2NPs stressed leaves. At the molecular level, RT-PCR analysis showed that K2SiO3 and SiO2NPs treatments stimulated the overexpression of PsbH, PsbB, and PsbD genes. Notably, this investigation indicated that K2SiO3 was more effective in improving wheat thermotolerance compared to SiO2NPs. The application of K2SiO3 and SiO2NPs may be one of the proposed approaches to improve crop growth and productivity to tolerate climatic change.

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