1
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Boytsov D, Madej GM, Horn G, Blaha N, Köcher T, Sitte HH, Siekhaus D, Ziegler C, Sandtner W, Roblek M. Orphan lysosomal solute carrier MFSD1 facilitates highly selective dipeptide transport. Proc Natl Acad Sci U S A 2024; 121:e2319686121. [PMID: 38507452 PMCID: PMC10990142 DOI: 10.1073/pnas.2319686121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/27/2024] [Indexed: 03/22/2024] Open
Abstract
Orphan solute carrier (SLC) represents a group of membrane transporters whose exact functions and substrate specificities are not known. Elucidating the function and regulation of orphan SLC transporters is not only crucial for advancing our knowledge of cellular and molecular biology but can potentially lead to the development of new therapeutic strategies. Here, we provide evidence for the biological function of a ubiquitous orphan lysosomal SLC, the Major Facilitator Superfamily Domain-containing Protein 1 (MFSD1), which has remained phylogenetically unassigned. Targeted metabolomics revealed that dipeptides containing either lysine or arginine residues accumulate in lysosomes of cells lacking MFSD1. Whole-cell patch-clamp electrophysiological recordings of HEK293-cells expressing MFSD1 on the cell surface displayed transport affinities for positively charged dipeptides in the lower mM range, while dipeptides that carry a negative net charge were not transported. This was also true for single amino acids and tripeptides, which MFSD1 failed to transport. Our results identify MFSD1 as a highly selective lysosomal lysine/arginine/histidine-containing dipeptide exporter, which functions as a uniporter.
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Affiliation(s)
- Danila Boytsov
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, ViennaAT-1090, Austria
| | - Gregor M. Madej
- Department of Biophysics II/Structural Biology, University of Regensburg, RegensburgDE-93053, Germany
| | - Georg Horn
- Department of Biophysics II/Structural Biology, University of Regensburg, RegensburgDE-93053, Germany
| | - Nadine Blaha
- Vienna BioCenter Core Facilities, Metabolomics, Vienna BioCenter, ViennaAT-1030, Austria
| | - Thomas Köcher
- Vienna BioCenter Core Facilities, Metabolomics, Vienna BioCenter, ViennaAT-1030, Austria
| | - Harald H. Sitte
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, ViennaAT-1090, Austria
- Hourani Center for Applied Scientific Research, Al-Ahliyya Amman University, AmmanJO-19328, Jordan
- Center for Addiction Research and Science, Medical University of Vienna, ViennaAT-1090, Austria
| | - Daria Siekhaus
- Institute of Science and Technology Austria, KlosterneuburgAT-3400, Austria
| | - Christine Ziegler
- Department of Biophysics II/Structural Biology, University of Regensburg, RegensburgDE-93053, Germany
| | - Walter Sandtner
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, ViennaAT-1090, Austria
| | - Marko Roblek
- Institute of Pharmacology, Center for Physiology and Pharmacology, Medical University of Vienna, ViennaAT-1090, Austria
- Institute of Science and Technology Austria, KlosterneuburgAT-3400, Austria
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2
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Fatima S, Khan MO, Iqbal N, Iqbal MM, Qamar H, Imtiaz M, Hundleby P, Wei Z, Ahmad N. Studying Salt-Induced Shifts in Gene Expression Patterns of Glucosinolate Transporters and Glucosinolate Accumulation in Two Contrasting Brassica Species. Metabolites 2024; 14:179. [PMID: 38668307 PMCID: PMC11052333 DOI: 10.3390/metabo14040179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 03/13/2024] [Accepted: 03/15/2024] [Indexed: 04/28/2024] Open
Abstract
Brassica crops are well known for the accumulation of glucosinolates-secondary metabolites crucial for plants' adaptation to various stresses. Glucosinolates also functioning as defence compounds pose challenges to food quality due to their goitrogenic properties. Their disruption leaves plants susceptible to insect pests and diseases. Hence, a targeted reduction in seed glucosinolate content is of paramount importance to increase food acceptance. GLUCOSINOLATE TRANSPORTERS (GTRs) present a promising avenue for selectively reducing glucosinolate concentrations in seeds while preserving biosynthesis elsewhere. In this study, 54 putative GTR protein sequences found in Brassica were retrieved, employing Arabidopsis GTR1 and GTR2 templates. Comprehensive bioinformatics analyses, encompassing gene structure organization, domain analysis, motif assessments, promoter analysis, and cis-regulatory elements, affirmed the existence of transporter domains and stress-related regulatory elements. Phylogenetic analysis revealed patterns of conservation and divergence across species. Glucosinolates have been shown to increase under stress conditions, indicating a potential role in stress response. To elucidate the role of GTRs in glucosinolate transportation under NaCl stress in two distinct Brassica species, B. juncea and B. napus, plants were subjected to 0, 100, or 200 mM NaCl. Based on the literature, key GTR genes were chosen and their expression across various plant parts was assessed. Both species displayed divergent trends in their biochemical profiles as well as glucosinolate contents under elevated salt stress conditions. Statistical modelling identified significant contributors to glucosinolate variations, guiding the development of targeted breeding strategies for low-glucosinolate varieties. Notably, GTR2A2 exhibited pronounced expressions in stems, contributing approximately 52% to glucosinolate content variance, while GTR2B1/C2 displayed significant expression in flowers. Additionally, GTR2A1 and GTR1A2/B1 demonstrated noteworthy expression in roots. This study enhances our understanding of glucosinolate regulation under stress conditions, offering avenues to improve Brassica crop quality and resilience.
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Affiliation(s)
- Samia Fatima
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
| | - Muhammad Omar Khan
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
| | - Nadia Iqbal
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
| | - Muhammad Mudassar Iqbal
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
| | - Huma Qamar
- Oilseeds Research Institute, Ayub Agricultural Research Institute, Faisalabad 38000, Pakistan;
- School of Biological Sciences, The University of Western Australia, Crawley, WA 6009, Australia
| | - Muhammad Imtiaz
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
| | - Penny Hundleby
- Department of Crop Genetics, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK;
| | - Zhengyi Wei
- Maize Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China
| | - Niaz Ahmad
- National Institute for Biotechnology and Genetic Engineering College (NIBGE-C), Pakistan Institute for Engineering and Applied Sciences (PIEAS), Faisalabad 38000, Pakistan; (S.F.); (M.O.K.); (N.I.); (M.M.I.); (M.I.)
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3
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Luo W, Tang J, Wang B, Wu D, Wang J, Cheng L, Geng F. The potential mechanism of low-power water bath ultrasound to enhance the effectiveness of low-concentration chlorine dioxide in inhibiting Salmonella Typhimurium. Food Chem X 2023; 20:100901. [PMID: 38144795 PMCID: PMC10740011 DOI: 10.1016/j.fochx.2023.100901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/24/2023] [Accepted: 09/23/2023] [Indexed: 12/26/2023] Open
Abstract
This chapter presents a systematic study of the inhibition effect of chlorine dioxide treatment alone and in combination with ultrasound treatment of Salmonella and the physiological metabolic processes within the treated cells. The low-power ultrasound (0.03 W/mL) significantly enhanced the effectiveness (110.00 %) of low concentrations of chlorine dioxide (0.25 mg/L) in inhibiting Salmonella, which, in turn, would significantly reduce the potential environmental impact. In addition, further studies found that low-power ultrasound may enhance the structural and functional damage of chlorine dioxide on Salmonella cell membranes (significant increase in permeability of the outer and inner cell membranes) and disrupt intracellular substance metabolism (small molecule and nucleotide metabolism) and energy metabolism (significant reduction in ATP content and ATPase activity) balance to improve the bacterial inhibitory effect of chlorine dioxide. The results of the study will provide a theoretical basis and methodological guidance for the implementation of "cleaner production" in the food industry.
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Affiliation(s)
- Wei Luo
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
| | - Jie Tang
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
| | - Beibei Wang
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
| | - Di Wu
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
| | - Jinqiu Wang
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
| | - Lei Cheng
- School of Food and Health, Beijing Technology & Business University (BTBU), Beijing 100048, China
| | - Fang Geng
- Institute for Egg Science and Technology, School of Food and Biological Engineering, Chengdu University, 2025 Chengluo Avenue, Chengdu, China
- Meat Processing Key Laboratory of Sichuan Province, School of Food and Biological Engineering, Chengdu University, No. 2025 Chengluo Avenue, Chengdu 610106, China
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4
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Feng J, Zhu C, Cao J, Liu C, Zhang J, Cao F, Zhou X. Genome-wide identification and expression analysis of the NRT genes in Ginkgo biloba under nitrate treatment reveal the potential roles during calluses browning. BMC Genomics 2023; 24:633. [PMID: 37872493 PMCID: PMC10594704 DOI: 10.1186/s12864-023-09732-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 10/11/2023] [Indexed: 10/25/2023] Open
Abstract
Nitrate is a primary nitrogen source for plant growth, and previous studies have indicated a correlation between nitrogen and browning. Nitrate transporters (NRTs) are crucial in nitrate allocation. Here, we utilized a genome-wide approach to identify and analyze the expression pattern of 74 potential GbNRTs under nitrate treatments during calluses browning in Ginkgo, including 68 NITRATE TRANSPORTER 1 (NRT1)/PEPTIDE TRANSPORTER (PTR) (NPF), 4 NRT2 and 2 NRT3. Conserved domains, motifs, phylogeny, and cis-acting elements (CREs) were analyzed to demonstrate the evolutionary conservation and functional diversity of GbNRTs. Our analysis showed that the NPF family was divided into eight branches, with the GbNPF2 and GbNPF6 subfamilies split into three groups. Each GbNRT contained 108-214 CREs of 19-36 types, especially with binding sites of auxin and transcription factors v-myb avian myeloblastosis viral oncogene homolog (MYB) and basic helix-loop-helix (bHLH). The E1X1X2E2R motif had significant variations in GbNPFs, indicating changes in the potential dynamic proton transporting ability. The expression profiles of GbNRTs indicated that they may function in regulating nitrate uptake and modulating the signaling of auxin and polyphenols biosynthesis, thereby affecting browning in Ginkgo callus induction. These findings provide a better understanding of the role of NRTs during NO3- uptake and utilization in vitro culture, which is crucial to prevent browning and develop an efficient regeneration and suspension production system in Ginkgo.
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Affiliation(s)
- Jin Feng
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Can Zhu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Jiaqi Cao
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Chen Liu
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Jiaqi Zhang
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
| | - Fuliang Cao
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
| | - Xiaohong Zhou
- State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Lin'an, Hangzhou, 311300, Zhejiang, China.
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5
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Structural basis of organic cation transporter-3 inhibition. Nat Commun 2022; 13:6714. [PMID: 36344565 PMCID: PMC9640557 DOI: 10.1038/s41467-022-34284-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 10/19/2022] [Indexed: 11/09/2022] Open
Abstract
Organic cation transporters (OCTs) facilitate the translocation of catecholamines, drugs and xenobiotics across the plasma membrane in various tissues throughout the human body. OCT3 plays a key role in low-affinity, high-capacity uptake of monoamines in most tissues including heart, brain and liver. Its deregulation plays a role in diseases. Despite its importance, the structural basis of OCT3 function and its inhibition has remained enigmatic. Here we describe the cryo-EM structure of human OCT3 at 3.2 Å resolution. Structures of OCT3 bound to two inhibitors, corticosterone and decynium-22, define the ligand binding pocket and reveal common features of major facilitator transporter inhibitors. In addition, we relate the functional characteristics of an extensive collection of previously uncharacterized human genetic variants to structural features, thereby providing a basis for understanding the impact of OCT3 polymorphisms.
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6
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Ye M, Qi X, Ren X, Quan W, Xu H, Zeng M, Chen J, Li M. Absorption and transport of myofibrillar protein-bound Nɛ-(carboxymethyl)lysine in Caco-2 cells after simulated gastrointestinal digestion. Food Res Int 2022; 161:111870. [DOI: 10.1016/j.foodres.2022.111870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/05/2022] [Accepted: 08/22/2022] [Indexed: 11/04/2022]
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7
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Wang C, Chu C, Ji X, Luo G, Xu C, He H, Yao J, Wu J, Hu J, Jin Y. Biology of Peptide Transporter 2 in Mammals: New Insights into Its Function, Structure and Regulation. Cells 2022; 11:cells11182874. [PMID: 36139448 PMCID: PMC9497230 DOI: 10.3390/cells11182874] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/09/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
Peptide transporter 2 (PepT2) in mammals plays essential roles in the reabsorption and conservation of peptide-bound amino acids in the kidney and in maintaining neuropeptide homeostasis in the brain. It is also of significant medical and pharmacological significance in the absorption and disposing of peptide-like drugs, including angiotensin-converting enzyme inhibitors, β-lactam antibiotics and antiviral prodrugs. Understanding the structure, function and regulation of PepT2 is of emerging interest in nutrition, medical and pharmacological research. In this review, we provide a comprehensive overview of the structure, substrate preferences and localization of PepT2 in mammals. As PepT2 is expressed in various organs, its function in the liver, kidney, brain, heart, lung and mammary gland has also been addressed. Finally, the regulatory factors that affect the expression and function of PepT2, such as transcriptional activation and posttranslational modification, are also discussed.
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Affiliation(s)
- Caihong Wang
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China
- Department of Bioinformatics, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
| | - Chu Chu
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Xiang Ji
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Guoliang Luo
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
| | - Chunling Xu
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
| | - Houhong He
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
| | - Jianbiao Yao
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
| | - Jian Wu
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
| | - Jiangning Hu
- Zhejiang Conba Pharmaceutical Limited Company, Hangzhou 310052, China
- Zhejiang Institute of Modern Chinese Medicine and Natural Medicine, Hangzhou 310052, China
- Correspondence: (J.H.); (Y.J.)
| | - Yuanxiang Jin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, China
- Correspondence: (J.H.); (Y.J.)
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8
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Genome-wide analysis of PTR transporters in Candida species and their functional characterization in Candida auris. Appl Microbiol Biotechnol 2022; 106:4223-4235. [PMID: 35648145 DOI: 10.1007/s00253-022-11998-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 05/14/2022] [Accepted: 05/16/2022] [Indexed: 11/02/2022]
Abstract
The peptide transport (PTR) or proton-dependent oligopeptide transporter (POT) family exploits the inwardly directed proton motive force to facilitate the cellular uptake of di/tripeptides. Interestingly, some representatives are also shown to import peptide-based antifungals in certain Candida species. Thus, the identification and characterization of PTR transporters serve as an essential first step for their potential usage as antifungal peptide uptake systems. Herein, we present a genome-wide inventory of the PTR transporters in five prominent Candida species. Our study identifies 2 PTR transporters each in C. albicans and C. dubliniensis, 1 in C. glabrata, 4 in C. parapsilosis, and 3 in C. auris. Notably, despite all representatives retaining the conserved features seen in the PTR family, there exist two distinct classes of PTR transporters that differ in terms of their sequence identities and lengths of certain extracellular and intracellular segments. Further, we also evaluated the contribution of each PTR protein of the newly emerged multi-drug-resistant C. auris in di/tripeptide uptake. Notably, deletion of two PTR genes BNJ08_003830 and BNJ08_005124 led to a marked reduction in the transport capabilities of several tested di/tripeptides. However, all three genes could complement the role of native PTR2 gene of Saccharomyces cerevisiae, albeit to varied levels. Besides, BNJ08_005124 deletion also resulted in increased resistance toward the peptide-nucleoside drug Nikkomycin Z as well as the glucosamine-6-phosphate synthase inhibitor, L-norvalyl-N3-(4-methoxyfumaroyl)-L-2,3-diaminopropionoic acid (Nva-FMDP), pointing toward its predominant role in their uptake mechanism. Altogether, the study provides an important template for future structure-function investigations of PTR transporters in Candida species. KEY POINTS: • Candida genome encodes for two distinct classes of PTR transporters. • Candida auris encodes for 3 PTR transporters with different specificities. • BNJ08_005124 in C. auris is involved in the uptake of Nikkomycin Z and Nva-FMDP.
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9
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Wu D, Zhang Y, Li J, Fan Z, Xu Q, Wang L. Assessment of chicken intestinal hydrolysates as a new protein source to replace fishmeal on the growth performance, antioxidant capacity and intestinal health of common carp (Cyprinus carpio). FISH & SHELLFISH IMMUNOLOGY 2022; 125:161-170. [PMID: 35561948 DOI: 10.1016/j.fsi.2022.05.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/06/2022] [Accepted: 05/08/2022] [Indexed: 06/15/2023]
Abstract
Promoting circular economy by transforming food residues into alternative high-value protein sources for aquaculture feed is a new way to develop alternative raw materials for fishmeal. This study systematically evaluated the effects of chicken intestinal hydrolysates (CIH) on the intestinal immune health of common carp through growth performance, antioxidant capacity, and intestinal immunity analysis in order to replace fishmeal. Five iso-nitrogenous and iso-lipidic experimental feeds were formulated to replace 0% (CIH-0), 25% (CIH-25), 50% (CIH-50), 75% (CIH-75) and 100% (CIH-100) of the fishmeal with CIH. Each experimental diet was fed to triplicate groups of 30 carp for 8 weeks. The results revealed that no significant differences in the final body weight, weight gain rate, feed coefficient radio, feed intake and protein efficiency ratio were found among the CIH-0, CIH-25, and CIH-50 groups, while the final body weight and weight gain rate in the CIH-75 and CIH-100 groups were significantly decreased and the feed coefficient radio was significantly increased. The aspartate aminotransferase of all CIH groups were significantly decrease, and the total protein, albumin did not differ among the CIH-0, CIH-25, CIH-50, and CIH-75 groups. The trypsin content was significantly increased in the CIH-75 and CIH-100 groups. No significant differences in the antioxidant index (catalase, glutathione peroxidase and malonaldehyde) were found among all CIH groups compared with the CIH-0 group. The expression levels of pro-inflammatory cytokines IL-1β and TNF-α were significantly down-regulated in the CIH-50 group and anti-inflammatory cytokines IL-10 and TGF-β2 were significantly up-regulated in the CIH-50 and CIH-75 groups. No significant differences in the expression levels of claudin-1, claudin-7 and claudin-11 were observed between the CIH-0 and CIH-50 groups, while the expression levels of ZO-1, occludin and MLCK were significantly up-regulated in the CIH-50 group compared with the CIH-0 group. The expression level of claudin-1 was down-regulated in the CIH-75 and CIH-100 groups. Hence, the study demonstrated the potential of CIH as a novel protein source for replacing fishmeal, and replacing 50% of fishmeal with CIH did not significantly influence the growth performance, immune responses, and intestinal barrier of common carp (Cyprinus carpio).
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Affiliation(s)
- Di Wu
- Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, 150070, China
| | - Yuanyuan Zhang
- Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, 150070, China
| | - Jinnan Li
- Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, 150070, China
| | - Ze Fan
- Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, 150070, China
| | - Qiyou Xu
- School of Life Science, Huzhou University, Huzhou, 313000, China
| | - Liansheng Wang
- Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin, 150070, China.
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10
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Proton Coupling and the Multiscale Kinetic Mechanism of a Peptide Transporter. Biophys J 2022; 121:2266-2278. [PMID: 35614850 DOI: 10.1016/j.bpj.2022.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/13/2022] [Accepted: 05/19/2022] [Indexed: 11/02/2022] Open
Abstract
Proton coupled peptide transporters (POTs) are crucial for the uptake of di- and tri-peptides as well as drug and pro-drug molecules in prokaryotes and eukaryotic cells. We illustrate from multiscale modeling how transmembrane proton flux couples within a POT protein to drive essential steps of the full functional cycle: 1) protonation of a glutamate on transmembrane helix (TM) 7 opens the extracellular gate, allowing ligand entry; 2) inward proton flow induces the cytosolic release of ligand by varying the protonation state of a second conserved glutamate on TM10; 3) proton movement between TM7 and TM10 is thermodynamically driven and kinetically permissible via water proton shuttling without the participation of ligand. Our results, for the first time, give direct computational confirmation for the alternating access model of POTs, and point to a quantitative multiscale kinetic picture of the functioning protein mechanism.
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11
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Stauffer M, Jeckelmann JM, Ilgü H, Ucurum Z, Boggavarapu R, Fotiadis D. Peptide transporter structure reveals binding and action mechanism of a potent PEPT1 and PEPT2 inhibitor. Commun Chem 2022; 5:23. [PMID: 36697632 PMCID: PMC9814568 DOI: 10.1038/s42004-022-00636-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/27/2022] [Indexed: 01/28/2023] Open
Abstract
Inhibitors for membrane transporters have been shown to be indispensable as drugs and tool compounds. The proton-dependent oligopeptide transporters PEPT1 and PEPT2 from the SLC15 family play important roles in human and mammalian physiology. With Lys[Z(NO2)]-Val (LZNV), a modified Lys-Val dipeptide, a potent transport inhibitor for PEPT1 and PEPT2 is available. Here we present the crystal structure of the peptide transporter YePEPT in complex with LZNV. The structure revealed the molecular interactions for inhibitor binding and a previously undescribed mostly hydrophobic pocket, the PZ pocket, involved in interaction with LZNV. Comparison with a here determined ligand-free structure of the transporter unveiled that the initially absent PZ pocket emerges through conformational changes upon inhibitor binding. The provided biochemical and structural information constitutes an important framework for the mechanistic understanding of inhibitor binding and action in proton-dependent oligopeptide transporters.
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Affiliation(s)
- Mirko Stauffer
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Jean-Marc Jeckelmann
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Hüseyin Ilgü
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Zöhre Ucurum
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
| | - Rajendra Boggavarapu
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland ,grid.67105.350000 0001 2164 3847Present Address: Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH USA
| | - Dimitrios Fotiadis
- grid.5734.50000 0001 0726 5157Institute of Biochemistry and Molecular Medicine, and Swiss National Centre of Competence in Research (NCCR) TransCure, University of Bern, Bern, Switzerland
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12
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Peña-Varas C, Kanstrup C, Vergara-Jaque A, González-Avendaño M, Crocoll C, Mirza O, Dreyer I, Nour-Eldin H, Ramírez D. Structural Insights into the Substrate Transport Mechanisms in GTR Transporters through Ensemble Docking. Int J Mol Sci 2022; 23:ijms23031595. [PMID: 35163519 PMCID: PMC8836200 DOI: 10.3390/ijms23031595] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/11/2022] [Accepted: 01/19/2022] [Indexed: 02/04/2023] Open
Abstract
Glucosinolate transporters (GTRs) are part of the nitrate/peptide transporter (NPF) family, members of which also transport specialized secondary metabolites as substrates. Glucosinolates are defense compounds derived from amino acids. We selected 4-methylthiobutyl (4MTB) and indol-3-ylmethyl (I3M) glucosinolates to study how GTR1 from Arabidopsis thaliana transports these substrates in computational simulation approaches. The designed pipeline reported here includes massive docking of 4MTB and I3M in an ensemble of GTR1 conformations (in both inward and outward conformations) extracted from molecular dynamics simulations, followed by clustered and substrate–protein interactions profiling. The identified key residues were mutated, and their role in substrate transport was tested. We were able to identify key residues that integrate a major binding site of these substrates, which is critical for transport activity. In silico approaches employed here represent a breakthrough in the plant transportomics field, as the identification of key residues usually takes a long time if performed from a purely wet-lab experimental perspective. The inclusion of structural bioinformatics in the analyses of plant transporters significantly speeds up the knowledge-gaining process and optimizes valuable time and resources.
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Affiliation(s)
- Carlos Peña-Varas
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Llano Subercaseaux 2801-piso 6, Santiago 8900000, Chile;
| | - Christa Kanstrup
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - Ariela Vergara-Jaque
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Mariela González-Avendaño
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Christoph Crocoll
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - Osman Mirza
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2200 Copenhagen, Denmark;
| | - Ingo Dreyer
- Center for Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Campus Talca, Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile; (A.V.-J.); (M.G.-A.); (I.D.)
| | - Hussam Nour-Eldin
- DynaMo Center, Department of Plant and Environmental Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; (C.K.); (C.C.); (H.N.-E.)
| | - David Ramírez
- Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Llano Subercaseaux 2801-piso 6, Santiago 8900000, Chile;
- Research Center for the Development of Novel Therapeutic Alternatives for Alcohol Use Disorders, Santiago 8900000, Chile
- Correspondence: ; Tel.: +56-(22)-3036667
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13
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Chemically Defined Formulas, Symbiotics and Cow's Milk Protein Allergy. Nutrients 2022; 14:nu14020299. [PMID: 35057480 PMCID: PMC8781908 DOI: 10.3390/nu14020299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 01/07/2022] [Indexed: 11/17/2022] Open
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14
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Urbizo-Reyes U, Liceaga AM, Reddivari L, Kim KH, Anderson JM. Enzyme kinetics, molecular docking, and in silico characterization of canary seed (Phalaris canariensis L.) peptides with ACE and pancreatic lipase inhibitory activity. J Funct Foods 2022. [DOI: 10.1016/j.jff.2021.104892] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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15
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Immadisetty K, Moradi M. Mechanistic Picture for Chemomechanical Coupling in a Bacterial Proton-Coupled Oligopeptide Transporter from Streptococcus Thermophilus. J Phys Chem B 2021; 125:9738-9750. [PMID: 34424716 DOI: 10.1021/acs.jpcb.1c03982] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Proton-coupled oligopeptide transporters (POTs) use the proton electrochemical gradient to transport peptides across the cell membrane. Despite the significant biological and biomedical relevance of these proteins, a detailed mechanistic picture for chemomechanical couplings involved in substrate/proton transport and protein structural changes is missing. Therefore, we performed microsecond-level molecular dynamics simulations of bacterial POT PepTSt, which shares ∼80% sequence identity with the human POT, PepT1, in the substrate-binding region. Three different conformational states of PepTSt were simulated, including (i) occluded, apo, (ii) inward-facing, apo, and (iii) inward-facingoccluded, Leu-Ala bound. We propose that the interaction of R33 with E299 and E300 acts as a conformational switch (i.e., to trigger the conformational change from an inward- to outward-facing state) in the substrate transport. Additionally, we propose that E299 and E400 disengage from interacting with the substrate either through protonation or through coordination with a cation for the substrate to get transported. This study provides clues to understand the chemomechanical couplings in POTs and paves the way to decipher the molecular-level underpinnings of the structure-function relationship in this important family of transporters.
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Affiliation(s)
| | - Mahmoud Moradi
- University of Arkansas, Fayetteville, Arkansas 72701, United States
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16
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Stauffer M, Ucurum Z, Harder D, Fotiadis D. Engineering and functional characterization of a proton-driven β-lactam antibiotic translocation module for bionanotechnological applications. Sci Rep 2021; 11:17205. [PMID: 34446740 PMCID: PMC8390754 DOI: 10.1038/s41598-021-96298-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/23/2021] [Indexed: 12/02/2022] Open
Abstract
Novel approaches in synthetic biology focus on the bottom-up modular assembly of natural, modified natural or artificial components into molecular systems with functionalities not found in nature. A possible application for such techniques is the bioremediation of natural water sources contaminated with small organic molecules (e.g., drugs and pesticides). A simple molecular system to actively accumulate and degrade pollutants could be a bionanoreactor composed of a liposome or polymersome scaffold combined with energizing- (e.g., light-driven proton pump), transporting- (e.g., proton-driven transporter) and degrading modules (e.g., enzyme). This work focuses on the engineering of a transport module specific for β-lactam antibiotics. We previously solved the crystal structure of a bacterial peptide transporter, which allowed us to improve the affinity for certain β-lactam antibiotics using structure-based mutagenesis combined with a bacterial uptake assay. We were able to identify specific mutations, which enhanced the affinity of the transporter for antibiotics containing certain structural features. Screening of potential compounds allowed for the identification of a β-lactam antibiotic ligand with relatively high affinity. Transport of antibiotics was evaluated using a solid-supported membrane electrophysiology assay. In summary, we have engineered a proton-driven β-lactam antibiotic translocation module, contributing to the growing toolset for bionanotechnological applications.
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Affiliation(s)
- Mirko Stauffer
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Zöhre Ucurum
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Daniel Harder
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland
| | - Dimitrios Fotiadis
- Institute of Biochemistry and Molecular Medicine, University of Bern, 3012, Bern, Switzerland.
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17
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Yu YC, Dickstein R, Longo A. Structural Modeling and in planta Complementation Studies Link Mutated Residues of the Medicago truncatula Nitrate Transporter NPF1.7 to Functionality in Root Nodules. FRONTIERS IN PLANT SCIENCE 2021; 12:685334. [PMID: 34276736 PMCID: PMC8282211 DOI: 10.3389/fpls.2021.685334] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/17/2021] [Indexed: 05/25/2023]
Abstract
Symbiotic nitrogen fixation is a complex and regulated process that takes place in root nodules of legumes and allows legumes to grow in soils that lack nitrogen. Nitrogen is mostly acquired from the soil as nitrate and its level in the soil affects nodulation and nitrogen fixation. The mechanism(s) by which legumes modulate nitrate uptake to regulate nodule symbiosis remain unclear. In Medicago truncatula, the MtNPF1.7 transporter has been shown to control nodulation, symbiosis, and root architecture. MtNPF1.7 belongs to the nitrate/peptide transporter family and is a symporter with nitrate transport driven by proton(s). In this study we combined in silico structural predictions with in planta complementation of the severely defective mtnip-1 mutant plants to understand the role of a series of distinct amino acids in the transporter's function. Our results support hypotheses about the functional importance of the ExxE(R/K) motif including an essential role for the first glutamic acid of the motif in proton(s) and possibly substrate transport. Results reveal that Motif A, a motif conserved among major facilitator transport (MFS) proteins, is essential for function. We hypothesize that it participates in intradomain packing of transmembrane helices and stabilizing one conformation during transport. Our results also question the existence of a putative TMH4-TMH10 salt bridge. These results are discussed in the context of potential nutrient transport functions for MtNPF1.7. Our findings add to the knowledge of the mechanism of alternative conformational changes as well as symport transport in NPFs and enhance our knowledge of the mechanisms for nitrate signaling.
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18
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Santin A, Caputi L, Longo A, Chiurazzi M, Ribera d'Alcalà M, Russo MT, Ferrante MI, Rogato A. Integrative omics identification, evolutionary and structural analysis of low affinity nitrate transporters in diatoms, diNPFs. Open Biol 2021; 11:200395. [PMID: 33823659 PMCID: PMC8025304 DOI: 10.1098/rsob.200395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Diatoms are one of the major and most diverse groups of phytoplankton, with chimeric genomes harbouring a combination of genes of bacterial, animal and plant origin. They have developed sophisticated mechanisms to face environmental variations. In marine environments, nutrients concentration shows significant temporal and spatial variability, influencing phytoplankton growth. Among nutrients, nitrogen, present at micromolar levels, is often a limiting resource. Here, we report a comprehensive characterization of the Nitrate Transporter 1/Peptide Transporter Family (NPF) in diatoms, diNPFs. NPFs are well characterized in many organisms where they recognize a broad range of substrates, ranging from short-chained di- and tri-peptides in bacteria, fungi and mammals to a wide variety of molecules including nitrate in higher plants. Scarce information is available for diNPFs. We integrated-omics, phylogenetic, structural and expression analyses, to infer information on their role in diatoms. diNPF genes diverged to produce two distinct clades with strong sequence and structural homology with either bacterial or plant NPFs, with different predicted sub-cellular localization, suggesting that the divergence resulted in functional diversification. Moreover, transcription analysis of diNPF genes under different laboratory and environmental growth conditions suggests that diNPF diversification led to genetic adaptations that might contribute to diatoms ability to flourish in diverse environmental conditions.
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Affiliation(s)
- Anna Santin
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Luigi Caputi
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy
| | - Antonella Longo
- BioDiscovery Institute, Denton, TX, USA.,Department of Biological Sciences, University of North Texas, Denton, TX, USA
| | - Maurizio Chiurazzi
- Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, 80131 Naples, Italy
| | | | | | | | - Alessandra Rogato
- Stazione Zoologica Anton Dohrn, Villa Comunale, 80121 Naples, Italy.,Institute of Biosciences and BioResources, CNR, Via P. Castellino 111, 80131 Naples, Italy
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19
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Fichtner F, Dissanayake IM, Lacombe B, Barbier F. Sugar and Nitrate Sensing: A Multi-Billion-Year Story. TRENDS IN PLANT SCIENCE 2021; 26:352-374. [PMID: 33281060 DOI: 10.1016/j.tplants.2020.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/23/2020] [Accepted: 11/04/2020] [Indexed: 05/03/2023]
Abstract
Sugars and nitrate play a major role in providing carbon and nitrogen in plants. Understanding how plants sense these nutrients is crucial, most notably for crop improvement. The mechanisms underlying sugar and nitrate sensing are complex and involve moonlighting proteins such as the nitrate transporter NRT1.1/NFP6.3 or the glycolytic enzyme HXK1. Major components of nutrient signaling, such as SnRK1, TOR, and HXK1, are relatively well conserved across eukaryotes, and the diversification of components such as the NRT1 family and the SWEET sugar transporters correlates with plant terrestrialization. In plants, Tre6P plays a hormone-like role in plant development. In addition, nutrient signaling has evolved to interact with the more recent hormone signaling, allowing fine-tuning of physiological and developmental responses.
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Affiliation(s)
- Franziska Fichtner
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia
| | | | - Benoit Lacombe
- Biochimie et Physiologie Moléculaire des Plantes (BPMP), Institut National de Recherche pour l'Agriculture, l'Alimentation, et l'Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS), Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Francois Barbier
- School of Biological Sciences, The University of Queensland, St. Lucia, QLD 4072, Australia.
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20
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Recent advances in understanding prodrug transport through the SLC15 family of proton-coupled transporters. Biochem Soc Trans 2021; 48:337-346. [PMID: 32219385 PMCID: PMC7200629 DOI: 10.1042/bst20180302] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 02/15/2020] [Accepted: 03/04/2020] [Indexed: 12/28/2022]
Abstract
Solute carrier (SLC) transporters play important roles in regulating the movement of small molecules and ions across cellular membranes. In mammals, they play an important role in regulating the uptake of nutrients and vitamins from the diet, and in controlling the distribution of their metabolic intermediates within the cell. Several SLC families also play an important role in drug transport and strategies are being developed to hijack SLC transporters to control and regulate drug transport within the body. Through the addition of amino acid and peptide moieties several novel antiviral and anticancer agents have been developed that hijack the proton-coupled oligopeptide transporters, PepT1 (SCL15A1) and PepT2 (SLC15A2), for improved intestinal absorption and renal retention in the body. A major goal is to understand the rationale behind these successes and expand the library of prodrug molecules that utilise SLC transporters. Recent co-crystal structures of prokaryotic homologues of the human PepT1 and PepT2 transporters have shed important new insights into the mechanism of prodrug recognition. Here, I will review recent developments in our understanding of ligand recognition and binding promiscuity within the SLC15 family, and discuss current models for prodrug recognition.
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21
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Xue L, Yin R, Howell K, Zhang P. Activity and bioavailability of food protein-derived angiotensin-I-converting enzyme-inhibitory peptides. Compr Rev Food Sci Food Saf 2021; 20:1150-1187. [PMID: 33527706 DOI: 10.1111/1541-4337.12711] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 12/11/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022]
Abstract
Angiotensin-I-converting enzyme (ACE) inhibitory peptides are able to inhibit the activity of ACE, which is the key enzymatic factor mediating systemic hypertension. ACE-inhibitory peptides can be obtained from edible proteins and have the function of antihypertension. The amino acid sequences and the secondary structures of ACE-inhibitory peptides determine the inhibitory activities and stability. The resistance of ACE-inhibitory peptides to digestive enzymes and peptidase affect their antihypertensive bioactivity in vivo. In this paper, the mechanism of ACE-inhibition, sources of the inhibitory peptides, structure-activity relationships, stability during digestion, absorption and transportation of ACE-inhibitory peptides, and consumption of ACE-inhibitory peptides are reviewed, which provide guidance to the development of new functional foods and production of antihypertensive nutraceuticals and pharmaceuticals.
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Affiliation(s)
- Lu Xue
- College of Biotechnology and Food Science, Tianjin University of Commerce, Tianjin, China.,School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Rongxin Yin
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Kate Howell
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
| | - Pangzhen Zhang
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Victoria, Australia
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22
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Tanaka M, Ito K, Matsuura T, Kawarasaki Y, Gomi K. Identification and distinct regulation of three di/tripeptide transporters in Aspergillus oryzae. Biosci Biotechnol Biochem 2020; 85:452-463. [DOI: 10.1093/bbb/zbaa030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/26/2020] [Indexed: 12/24/2022]
Abstract
ABSTRACT
The uptake of di/tripeptides is mediated by the proton-dependent oligopeptide transporter (POT) family. In this study, 3 POT family transporters, designated PotA, PotB, and PotC were identified in Aspergillus oryzae. Growth comparison of deletion mutants of these transporter genes suggested that PotB and PotC are responsible for di/tripeptide uptake. PotA, which had the highest sequence similarity to yeast POT (Ptr2), contributed little to the uptake. Nitrogen starvation induced potB and potC expression, but not potA expression. When 3 dipeptides were provided as nitrogen sources, the expression profiles of these genes were different. PrtR, a transcription factor that regulates proteolytic genes, was involved in regulation of potA and potB but not in potC expression. Only potC expression levels were dramatically reduced by disruption of ubrA, an orthologue of yeast ubiquitin ligase UBR1 responsible for PTR2 expression. Expression of individual POT genes is apparently controlled by different regulatory mechanisms.
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Affiliation(s)
- Mizuki Tanaka
- Biomolecular Engineering Laboratory, School of Food and Nutritional Science, University of Shizuoka, Suruga-ku, Shizuoka, Japan
| | - Keisuke Ito
- Laboratory of Food Chemistry, School of Food and Nutritional Science, University of Shizuoka, Suruga-ku, Shizuoka, Japan
| | - Tomomi Matsuura
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai, Japan
| | - Yasuaki Kawarasaki
- Biomolecular Engineering Laboratory, School of Food and Nutritional Science, University of Shizuoka, Suruga-ku, Shizuoka, Japan
| | - Katsuya Gomi
- Laboratory of Bioindustrial Genomics, Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai, Japan
- Laboratory of Fermentation Microbiology, Graduate School of Agricultural Science, Tohoku University, Aoba-ku, Sendai, Japan
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23
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Prabhala BK, Rahman M, Nour-Eldin HH, Jørgensen FS, Mirza O. PTR2/POT/NPF transporters: what makes them tick? ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 123:219-240. [PMID: 33485485 DOI: 10.1016/bs.apcsb.2020.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PTR2/POT/NPF are a family of primarily proton coupled transporters that belong to the major facilitator super family and are found across most kingdoms of life. They are involved in uptake of nutrients, hormones, ions and several orally administered drug molecules. A wealth of structural and functional data is available for this family; the similarity between the protein structural features have been discussed and investigated in detail on several occasions, however there are no reports on the unification of substrate information. In order to fill this gap, we have collected information about substrates across the entire PTR2/POT/NPF family in order to provide key insights into what makes a molecule a substrate and whether there are common features among confirmed substrates. This review will be of particular interest for researchers in the field trying to probe the mechanisms responsible for the different selectivity of these transporters at a molecular resolution, and to design novel substrates.
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Affiliation(s)
- Bala K Prabhala
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - Moazur Rahman
- School of Biological Sciences, University of the Punjab, Lahore, Punjab, Pakistan; Drug Discovery and Structural Biology Group, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), Faisalabad, Punjab, Pakistan
| | - Hussam H Nour-Eldin
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Flemming Steen Jørgensen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Osman Mirza
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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24
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Ferroptosis in Liver Diseases: An Overview. Int J Mol Sci 2020; 21:ijms21144908. [PMID: 32664576 PMCID: PMC7404091 DOI: 10.3390/ijms21144908] [Citation(s) in RCA: 176] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/03/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022] Open
Abstract
Ferroptosis is an iron-dependent form of cell death characterized by intracellular lipid peroxide accumulation and redox imbalance. Ferroptosis shows specific biological and morphological features when compared to the other cell death patterns. The loss of lipid peroxide repair activity by glutathione peroxidase 4 (GPX4), the presence of redox-active iron and the oxidation of polyunsaturated fatty acid (PUFA)-containing phospholipids are considered as distinct fingerprints of ferroptosis. Several pathways, including amino acid and iron metabolism, ferritinophagy, cell adhesion, p53, Keap1/Nrf2 and phospholipid biosynthesis, can modify susceptibility to ferroptosis. Through the decades, various diseases, including acute kidney injury; cancer; ischemia–reperfusion injury; and cardiovascular, neurodegenerative and hepatic disorders, have been associated with ferroptosis. In this review, we provide a comprehensive analysis of the main biological and biochemical mechanisms of ferroptosis and an overview of chemicals used as inducers and inhibitors. Then, we report the contribution of ferroptosis to the spectrum of liver diseases, acute or chronic. Finally, we discuss the use of ferroptosis as a therapeutic approach against hepatocellular carcinoma, the most common form of primary liver cancer.
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25
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Leveraging nature's biomolecular designs in next-generation protein sequencing reagent development. Appl Microbiol Biotechnol 2020; 104:7261-7271. [PMID: 32617618 DOI: 10.1007/s00253-020-10745-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/09/2020] [Accepted: 06/15/2020] [Indexed: 01/18/2023]
Abstract
Next-generation approaches for protein sequencing are now emerging that could have the potential to revolutionize the field in proteomics. One such sequencing method involves fluorescence-based imaging of immobilized peptides in which the N-terminal amino acid of a polypeptide is readout sequentially by a series of fluorescently labeled biomolecules. When selectively bound to a specific N-terminal amino acid, the NAAB (N-terminal amino acid binder) affinity reagent identifies the amino acid through its associated fluorescence tag. A key technical challenge in implementing this fluoro-sequencing approach is the need to develop NAAB affinity reagents with the high affinity and selectivity for specific N-terminal amino acids required for this biotechnology application. One approach to develop such a NAAB affinity reagent is to leverage naturally occurring biomolecules that bind amino acids and/or peptides. Here, we describe several candidate biomolecules that could be considered for this purpose and discuss the potential for developability of each. Key points • Next-generation sequencing methods are emerging that could revolutionize proteomics. • Sequential readout of N-terminal amino acids by fluorescent-tagged affinity reagents. • Native peptide/amino acid binders can be engineered into affinity reagents. • Protein size and structure contribute to feasibility of reagent developability.
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26
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Wang SC, Davejan P, Hendargo KJ, Javadi-Razaz I, Chou A, Yee DC, Ghazi F, Lam KJK, Conn AM, Madrigal A, Medrano-Soto A, Saier MH. Expansion of the Major Facilitator Superfamily (MFS) to include novel transporters as well as transmembrane-acting enzymes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183277. [PMID: 32205149 DOI: 10.1016/j.bbamem.2020.183277] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/14/2020] [Accepted: 03/17/2020] [Indexed: 12/14/2022]
Abstract
The Major Facilitator Superfamily (MFS) is currently the largest characterized superfamily of transmembrane secondary transport proteins. Its diverse members are found in essentially all organisms in the biosphere and function by uniport, symport, and/or antiport mechanisms. In 1993 we first named and described the MFS which then consisted of 5 previously known families that had not been known to be related, and by 2012 we had identified a total of 74 families, classified phylogenetically within the MFS, all of which included only transport proteins. This superfamily has since expanded to 89 families, all included under TC# 2.A.1, and a few transporter families outside of TC# 2.A.1 were identified as members of the MFS. In this study, we assign nine previously unclassified protein families in the Transporter Classification Database (TCDB; http://www.tcdb.org) to the MFS based on multiple criteria and bioinformatic methodologies. In addition, we find integral membrane domains distantly related to partial or full-length MFS permeases in Lysyl tRNA Synthases (TC# 9.B.111), Lysylphosphatidyl Glycerol Synthases (TC# 4.H.1), and cytochrome b561 transmembrane electron carriers (TC# 5.B.2). Sequence alignments, overlap of hydropathy plots, compatibility of repeat units, similarity of complexity profiles of transmembrane segments, shared protein domains and 3D structural similarities between transport proteins were analyzed to assist in inferring homology. The MFS now includes 105 families.
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Affiliation(s)
- Steven C Wang
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Pauldeen Davejan
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Kevin J Hendargo
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Ida Javadi-Razaz
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Amy Chou
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Daniel C Yee
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Faezeh Ghazi
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Katie Jing Kay Lam
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Adam M Conn
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Assael Madrigal
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Arturo Medrano-Soto
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America
| | - Milton H Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093-0116, United States of America.
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27
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A biotechnological approach for the production of branched chain amino acid containing bioactive peptides to improve human health: A review. Food Res Int 2020; 131:109002. [PMID: 32247480 DOI: 10.1016/j.foodres.2020.109002] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 12/21/2019] [Accepted: 01/12/2020] [Indexed: 12/20/2022]
Abstract
Improper nutrition provokes many types of chronic diseases and health problems, which consequently are associated with particularly high costs of treatments. Nowadays, consumer's interest in healthy eating is shifting towards specific foods or food ingredients. As a consequence, bioactive peptides as a promising source of health promoting food additives are currently an intensely debated topic in research. Process design is still on its early stages and is significantly influenced by important preliminary decisions. Thus, parameters like peptide bioactivity within the product, selection of the protein source, enzyme selection for hydrolysis, peptide enrichment method, as well as stability of the peptides within the food matrix and bioavailability are sensitive decision points, which have to be purposefully coordinated, as they are directly linked to amino acid content and structure properties of the peptides. Branched chain amino acids (BCAA) are essential components for humans, possessing various important physiologic functions within the body. Incorporated within peptide sequences, they may induce dual functions, when used as nutraceuticals in functional food, thus preserving the foodstuff and prevent several widespread diseases. Furthermore, there is evidence that consuming this peptide-class can be a nutritional support for elderly people or improve human health to prevent diseases caused by incorrect nutrition. Based on the knowledge about the role of BCAA within various peptide functions, discussed in the review, special attention is given to different approaches for systematic selection of the protein source and enzymes used in hydrolysis, as well as suitable peptide enrichment methods, thereby showing current trends in research.
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28
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Ohara-Nemoto Y, Sarwar MT, Shimoyama Y, Kobayakawa T, Nemoto TK. Preferential dipeptide incorporation of Porphyromonas gingivalis mediated by proton-dependent oligopeptide transporter (Pot). FEMS Microbiol Lett 2020; 367:6041718. [PMID: 33338236 DOI: 10.1093/femsle/fnaa204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 11/24/2020] [Indexed: 11/13/2022] Open
Abstract
Multiple dipeptidyl-peptidases (DPPs) are present in the periplasmic space of Porphyromonas gingivalis, an asaccharolytic periodontopathic bacterium. Dipeptides produced by DPPs are presumed to be transported into the bacterial cells and metabolized to generate energy and cellular components. The present study aimed to identify a transporter responsible for dipeptide uptake in the bacterium. A real-time metabolic analysis demonstrated that P. gingivalis preferentially incorporated Gly-Xaa dipeptides, and then, single amino acids, tripeptides and longer oligopeptides to lesser extents. Heterologous expression of the P. gingivalis serine/threonine transporter (SstT; PGN_1460), oligopeptide transporter (Opt; PGN_1518) and proton-dependent oligopeptide transporter (Pot; PGN_0135) genes demonstrated that Escherichia coli expressing Pot exclusively incorporated Gly-Gly, while SstT managed Ser uptake and Opt was responsible for Gly-Gly-Gly uptake. Dipeptide uptake was significantly decreased in a P. gingivalis Δpot strain and further suppressed in a Δpot-Δopt double-deficient strain. In addition, the growth of the Δpot strain was markedly attenuated and the Δpot-Δopt strain scarcely grew, whereas the ΔsstT strain grew well almost like wild type. Consequently, these results demonstrate that predominant uptake of dipeptide in P. gingivalis is mostly managed by Pot. We thus propose that Pot is a potential therapeutic target of periodontal disease and P. gingivalis-related systemic diseases.
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Affiliation(s)
- Yuko Ohara-Nemoto
- Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Mohammad Tanvir Sarwar
- Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Yu Shimoyama
- Division of Molecular Microbiology, Department of Microbiology, Iwate Medical University, 1-1-1 Idai-dori, Yahaba-cho, Iwate 028-3694, Japan
| | - Takeshi Kobayakawa
- Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
| | - Takayuki K Nemoto
- Department of Oral Molecular Biology, Course of Medical and Dental Sciences, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki 852-8588, Japan
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29
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Batista MRB, Watts A, José Costa-Filho A. Exploring Conformational Transitions and Free-Energy Profiles of Proton-Coupled Oligopeptide Transporters. J Chem Theory Comput 2019; 15:6433-6443. [PMID: 31639304 DOI: 10.1021/acs.jctc.9b00524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Proteins involved in peptide uptake and transport belong to the proton-coupled oligopeptide transporter (POT) family. Crystal structures of POT family members reveal a common fold consisting of two domains of six transmembrane α helices that come together to form a "V" shaped transporter with a central substrate binding site. Proton-coupled oligopeptide transporters operate through an alternate access mechanism, where the membrane transporter undergoes global conformational changes, alternating between inward-facing (IF), outward-facing (OF), and occluded (OC) states. Conformational transitions are promoted by proton and ligand binding; however, due to the absence of crystallographic models of the outward-open state, the role of H+ and ligands is still not fully understood. To provide a comprehensive picture of the POT conformational equilibrium, conventional and enhanced sampling molecular dynamics simulations of PepTst in the presence or absence of ligand and protonation were performed. Free-energy profiles of the conformational variability of PepTst were obtained from microseconds of adaptive biasing force (ABF) simulations. Our results reveal that both proton and ligand significantly change the conformational free-energy landscape. In the absence of ligand and protonation, only transitions involving IF and OC states are allowed. After protonation of the residue Glu300, the wider free-energy well for Glu300 protonated PepTst indicates a greater conformational variability relative to the apo system, and OF conformations became accessible. For the Glu300 protonated Holo-PepTst, the presence of a second free-energy minimum suggests that OF conformations are not only accessible, but also stable. The differences in the free-energy profiles demonstrate that transitions toward outward-facing conformation occur only after protonation, which is likely the first step in the mechanism of peptide transport. Our extensive ABF simulations provide a fully atomic description of all states of the transport process, offering a model for the alternating access mechanism and how protonation and ligand control the conformational changes.
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Affiliation(s)
- Mariana R B Batista
- Ribeirão Preto School of Philosophy, Sciences and Letters , University of São Paulo , Ribeirao Preto , São Paulo 14040901 , Brazil
| | - Anthony Watts
- Department of Biochemistry , University of Oxford , South Parks Road , Oxford OX1 2JD , United Kingdom
| | - Antonio José Costa-Filho
- Ribeirão Preto School of Philosophy, Sciences and Letters , University of São Paulo , Ribeirao Preto , São Paulo 14040901 , Brazil
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30
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Wulff N, Ernst HA, Jørgensen ME, Lambertz S, Maierhofer T, Belew ZM, Crocoll C, Motawia MS, Geiger D, Jørgensen FS, Mirza O, Nour-Eldin HH. An Optimized Screen Reduces the Number of GA Transporters and Provides Insights Into Nitrate Transporter 1/Peptide Transporter Family Substrate Determinants. FRONTIERS IN PLANT SCIENCE 2019; 10:1106. [PMID: 31632416 PMCID: PMC6785635 DOI: 10.3389/fpls.2019.01106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 08/13/2019] [Indexed: 05/17/2023]
Abstract
Based on recent in vitro data, a relatively large number of the plant nitrate transporter 1/peptide transporter family (NPF) proteins have been suggested to function as gibberellic acid (GA) transporters. Most GA transporting NPF proteins also appear to transport other structurally unrelated phytohormones or metabolites. Several of the GAs used in previous in vitro assays are membrane permeable weak organic acids whose movement across membranes are influenced by the pH-sensitive ion-trap mechanism. Moreover, a large proportion of in vitro GA transport activities have been demonstrated indirectly via long-term yeast-based GA-dependent growth assays that are limited to detecting transport of bioactive GAs. Thus, there is a need for an optimized transport assay for identifying and characterizing GA transport. Here, we develop an improved transport assay in Xenopus laevis oocytes, wherein we directly measure movement of six different GAs across oocyte membranes over short time. We show that membrane permeability of GAs in oocytes can be predicted based on number of oxygen atoms and that several GAs do not diffuse over membranes regardless of changes in pH values. In addition, we show that small changes in internal cellular pH can result in strongly altered distribution of membrane permeable phytohormones. This prompts caution when interpreting heterologous transport activities. We use our transport assay to screen all Arabidopsis thaliana NPF proteins for transport activity towards six GAs (two membrane permeable and four non-permeable). The results presented here, significantly reduce the number of bona fide NPF GA transporters in Arabidopsis and narrow the activity to fewer subclades within the family. Furthermore, to gain first insight into the molecular determinants of substrate specificities toward organic molecules transported in the NPF, we charted all surface exposed amino acid residues in the substrate-binding cavity and correlated them to GA transport. This analysis suggests distinct residues within the substrate-binding cavity that are shared between GA transporting NPF proteins; the potential roles of these residues in determining substrate specificity are discussed.
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Affiliation(s)
- Nikolai Wulff
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | | | - Morten Egevang Jørgensen
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
- Julius-von-Sachs-Institute, Molecular Plant Physiology and Biophysics, University Würzburg, Würzburg, Germany
- Carlsberg Research Laboratory, Copenhagen, Denmark
| | - Sophie Lambertz
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Tobias Maierhofer
- Julius-von-Sachs-Institute, Molecular Plant Physiology and Biophysics, University Würzburg, Würzburg, Germany
| | - Zeinu Mussa Belew
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Christoph Crocoll
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Mohammed Saddik Motawia
- Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Dietmar Geiger
- Julius-von-Sachs-Institute, Molecular Plant Physiology and Biophysics, University Würzburg, Würzburg, Germany
| | | | - Osman Mirza
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Hussam Hassan Nour-Eldin
- DynaMo Center, Copenhagen Plant Science Centre, Department of Plant and Environmental Sciences, University of Copenhagen, Frederiksberg, Denmark
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31
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Moeller FU, Webster NS, Herbold CW, Behnam F, Domman D, Albertsen M, Mooshammer M, Markert S, Turaev D, Becher D, Rattei T, Schweder T, Richter A, Watzka M, Nielsen PH, Wagner M. Characterization of a thaumarchaeal symbiont that drives incomplete nitrification in the tropical sponge Ianthella basta. Environ Microbiol 2019; 21:3831-3854. [PMID: 31271506 PMCID: PMC6790972 DOI: 10.1111/1462-2920.14732] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 12/25/2022]
Abstract
Marine sponges represent one of the few eukaryotic groups that frequently harbour symbiotic members of the Thaumarchaeota, which are important chemoautotrophic ammonia-oxidizers in many environments. However, in most studies, direct demonstration of ammonia-oxidation by these archaea within sponges is lacking, and little is known about sponge-specific adaptations of ammonia-oxidizing archaea (AOA). Here, we characterized the thaumarchaeal symbiont of the marine sponge Ianthella basta using metaproteogenomics, fluorescence in situ hybridization, qPCR and isotope-based functional assays. 'Candidatus Nitrosospongia ianthellae' is only distantly related to cultured AOA. It is an abundant symbiont that is solely responsible for nitrite formation from ammonia in I. basta that surprisingly does not harbour nitrite-oxidizing microbes. Furthermore, this AOA is equipped with an expanded set of extracellular subtilisin-like proteases, a metalloprotease unique among archaea, as well as a putative branched-chain amino acid ABC transporter. This repertoire is strongly indicative of a mixotrophic lifestyle and is (with slight variations) also found in other sponge-associated, but not in free-living AOA. We predict that this feature as well as an expanded and unique set of secreted serpins (protease inhibitors), a unique array of eukaryotic-like proteins, and a DNA-phosporothioation system, represent important adaptations of AOA to life within these ancient filter-feeding animals.
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Affiliation(s)
- Florian U. Moeller
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Nicole S. Webster
- Australian Institute of Marine ScienceTownsvilleQueenslandAustralia
- Australian Centre for Ecogenomics, School of Chemistry and Molecular BiosciencesUniversity of QueenslandSt LuciaQueenslandAustralia
| | - Craig W. Herbold
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Faris Behnam
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Daryl Domman
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Mads Albertsen
- Center for Microbial Communities, Department of Chemistry and BioscienceAalborg University9220AalborgDenmark
| | - Maria Mooshammer
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
| | - Stephanie Markert
- Institute of Marine Biotechnology e.VGreifswaldGermany
- Institute of Pharmacy, Pharmaceutical BiotechnologyUniversity of GreifswaldGreifswaldGermany
| | - Dmitrij Turaev
- Centre for Microbiology and Environmental Systems Science, Division of Computational Systems BiologyUniversity of ViennaAustria
| | - Dörte Becher
- Institute of Microbiology, Microbial ProteomicsUniversity of GreifswaldGreifswaldGermany
| | - Thomas Rattei
- Centre for Microbiology and Environmental Systems Science, Division of Computational Systems BiologyUniversity of ViennaAustria
| | - Thomas Schweder
- Institute of Marine Biotechnology e.VGreifswaldGermany
- Institute of Pharmacy, Pharmaceutical BiotechnologyUniversity of GreifswaldGreifswaldGermany
| | - Andreas Richter
- Centre for Microbiology and Environmental Systems Science, Division of Terrestrial Ecosystem ResearchUniversity of ViennaAustria
| | - Margarete Watzka
- Centre for Microbiology and Environmental Systems Science, Division of Terrestrial Ecosystem ResearchUniversity of ViennaAustria
| | - Per Halkjaer Nielsen
- Center for Microbial Communities, Department of Chemistry and BioscienceAalborg University9220AalborgDenmark
| | - Michael Wagner
- Centre for Microbiology and Environmental Systems Science, Division of Microbial EcologyUniversity of ViennaAustria
- Center for Microbial Communities, Department of Chemistry and BioscienceAalborg University9220AalborgDenmark
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32
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Wu Z, Alibay I, Newstead S, Biggin PC. Proton Control of Transitions in an Amino Acid Transporter. Biophys J 2019; 117:1342-1351. [PMID: 31500802 PMCID: PMC6818167 DOI: 10.1016/j.bpj.2019.07.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 07/03/2019] [Accepted: 07/30/2019] [Indexed: 12/19/2022] Open
Abstract
Amino acid transport into the cell is often coupled to the proton electrochemical gradient, as found in the solute carrier 36 family of proton-coupled amino acid transporters. Although no structure of a human proton-coupled amino acid transporter exists, the crystal structure of a related homolog from bacteria, GkApcT, has recently been solved in an inward-occluded state and allows an opportunity to examine how protons are coupled to amino acid transport. Our working hypothesis is that release of the amino acid substrate is facilitated by the deprotonation of a key glutamate residue (E115) located at the bottom of the binding pocket, which forms part of the intracellular gate, allowing the protein to transition from an inward-occluded to an inward-open conformation. During unbiased molecular dynamics simulations, we observed a transition from the inward-occluded state captured in the crystal structure to a much more open state, which we consider likely to be representative of the inward-open state associated with substrate release. To explore this and the role of protons in these transitions, we have used umbrella sampling to demonstrate that the transition from inward occluded to inward open is more energetically favorable when E115 is deprotonated. That E115 is likely to be protonated in the inward-occluded state and deprotonated in the inward-open state is further confirmed via the use of absolute binding free energies. Finally, we also show, via the use of absolute binding free energy calculations, that the affinity of the protein for alanine is very similar regardless of either the conformational state or the protonation of E115, presumably reflecting the fact that all the key interactions are deep within the binding cavity. Together, our results give a detailed picture of the role of protons in driving one of the major transitions in this transporter.
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Affiliation(s)
- Zhiyi Wu
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Irfan Alibay
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Simon Newstead
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Philip C Biggin
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom.
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33
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Fujii J, Homma T, Kobayashi S. Ferroptosis caused by cysteine insufficiency and oxidative insult. Free Radic Res 2019; 54:969-980. [PMID: 31505959 DOI: 10.1080/10715762.2019.1666983] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Free iron has long been assumed to be a deteriorating factor in an oxidative insult and was recently found to be directly associated with ferroptosis, a specific type of cell death. The free iron-involved production of lipid peroxides activates the fatal pathway, resulting in nonapoptotic, programed cell death. Lipid peroxides appear to destroy membrane integrity, leading to cell rupture. Glutathione (GSH) is a major redox molecule that functions to protect against ferroptosis by its ability to donate an electron to glutathione peroxidase 4 (GPX4), the sole enzyme that reduces phospholipid hydroperoxides. The availability of free cysteine (Cys) determines the levels of GSH synthesis, and, hence, its deprivation causes ferroptosis. Free iron is provided via ferritinophagy, the chaperone-mediated autophagic degradation of ferritin, but GPX4 also undergoes degradation via chaperone-mediated autophagy. Activated Nrf2 and ATF4 induce the expression of the cystine transporter xCT to cope with ferroptosis. To the contrary, the excessive activation of p53 induces ferroptosis by suppressing the expression of xCT in genetic and nongenetic manners. It therefore appears that xCT functions as the gatekeeper for determining cellular survival by regulating the availability of Cys in the cell. The issue of the extent of involvement of ferroptosis in an in vivo situation largely remains ambiguous. Establishing tools for specifying ferroptotic cells in situ would facilitate our understanding of its roles in pathogenesis.
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Affiliation(s)
- Junichi Fujii
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata City, Japan
| | - Takujiro Homma
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata City, Japan
| | - Sho Kobayashi
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata City, Japan
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34
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Rojas F, Matthews KR. Quorum sensing in African trypanosomes. Curr Opin Microbiol 2019; 52:124-129. [PMID: 31442903 DOI: 10.1016/j.mib.2019.07.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 06/28/2019] [Accepted: 07/17/2019] [Indexed: 01/17/2023]
Abstract
Many microbial eukaryotes exhibit cell-cell communication to co-ordinate group behaviours as a strategy to exploit a changed environment, adapt to adverse conditions or regulate developmental responses. Although best characterised in bacteria, eukaryotic microbes have also been revealed to cooperate to optimise their survival or dissemination. An excellent model for these processes are African trypanosomes, protozoa responsible for important human and animal disease in sub Saharan Africa. These unicellular parasites use density sensing in their mammalian host to prepare for transmission. Recently, the signal and signal transduction pathway underlying this activity have been elucidated, revealing that the parasite exploits oligopeptide signals generated by released peptidases to monitor cell density and so generate transmission stages. Here we review the evidence for this elegant quorum sensing mechanism and its parallels with similar mechanisms in other microbial systems. We also discuss its implications for disease spread in the context of coinfections involving different trypanosome species.
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Affiliation(s)
- Federico Rojas
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, United Kingdom.
| | - Keith R Matthews
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, United Kingdom.
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35
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Hamada K, Naito A, Hamaguchi Y, Kanesaki Y, Kasahara K, Taguchi A, Omura N, Hayashi Y, Usui T. Ubr1p-Cup9p-Ptr2p pathway involves in the sensitivity to readthrough compounds negamycin derivatives in budding yeast. Biosci Biotechnol Biochem 2019; 83:1889-1892. [PMID: 31159660 DOI: 10.1080/09168451.2019.1625263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
In this study, we found that dipeptide transporter Ptr2p is the putative transporter of read-through compounds (+)-negamycin derivatives TCP-126 and TCP-112, in budding yeast. Ptr2p expression and activity were correlated with the TCP-112 sensitivity, and dipeptide with high affinity to Ptr2p suppressed the TCP-112 activity. These results suggest that dipeptide transporter is one of the determinants of negamycin analogs sensitivity. Abbreviation: PTC: premature termination codon.
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Affiliation(s)
- Keisuke Hamada
- Department of Medicinal Chemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Tokyo , Japan
| | - Akari Naito
- Graduate School of Life and Environmental Sciences, University of Tsukuba , Tsukuba , Japan
| | - Yu Hamaguchi
- NODAI Genome Research Center, Tokyo University of Agriculture , Tokyo , Japan
| | - Yu Kanesaki
- NODAI Genome Research Center, Tokyo University of Agriculture , Tokyo , Japan
| | - Koji Kasahara
- Department of Molecular Microbiology, Tokyo University of Agriculture , Tokyo , Japan
| | - Akihiro Taguchi
- Department of Medicinal Chemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Tokyo , Japan
| | - Noriko Omura
- Department of Medicinal Chemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Tokyo , Japan
| | - Yoshio Hayashi
- Department of Medicinal Chemistry, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences , Tokyo , Japan
| | - Takeo Usui
- Faculty of Life and Environmental Sciences, University of Tsukuba , Tsukuba , Japan
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36
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Majumder P, Khare S, Athreya A, Hussain N, Gulati A, Penmatsa A. Dissection of Protonation Sites for Antibacterial Recognition and Transport in QacA, a Multi-Drug Efflux Transporter. J Mol Biol 2019; 431:2163-2179. [PMID: 30910733 PMCID: PMC7212025 DOI: 10.1016/j.jmb.2019.03.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 01/05/2023]
Abstract
QacA is a drug:H+ antiporter with 14 transmembrane helices that confers antibacterial resistance to methicillin-resistant Staphylococcus aureus strains, with homologs in other pathogenic organisms. It is a highly promiscuous antiporter, capable of H+-driven efflux of a wide array of cationic antibacterial compounds and dyes. Our study, using a homology model of QacA, reveals a group of six protonatable residues in its vestibule. Systematic mutagenesis resulted in the identification of D34 (TM1), and a cluster of acidic residues in TM13 including E407 and D411 and D323 in TM10, as being crucial for substrate recognition and transport of monovalent and divalent cationic antibacterial compounds. The transport and binding properties of QacA and its mutants were explored using whole cells, inside-out vesicles, substrate-induced H+ release and microscale thermophoresis-based assays. The activity of purified QacA was also observed using proteoliposome-based substrate-induced H+ transport assay. Our results identify two sites, D34 and D411 as vital players in substrate recognition, while E407 facilitates substrate efflux as a protonation site. We also observe that E407 plays an additional role as a substrate recognition site for the transport of dequalinium, a divalent quaternary ammonium compound. These observations rationalize the promiscuity of QacA for diverse substrates. The study unravels the role of acidic residues in QacA with implications for substrate recognition, promiscuity and processive transport in multidrug efflux transporters, related to QacA.
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Affiliation(s)
- Puja Majumder
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Shashank Khare
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Arunabh Athreya
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Nazia Hussain
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Ashutosh Gulati
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India
| | - Aravind Penmatsa
- Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560012, India.
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37
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Hohl M, Remm S, Eskandarian HA, Dal Molin M, Arnold FM, Hürlimann LM, Krügel A, Fantner GE, Sander P, Seeger MA. Increased drug permeability of a stiffened mycobacterial outer membrane in cells lacking MFS transporter Rv1410 and lipoprotein LprG. Mol Microbiol 2019; 111:1263-1282. [PMID: 30742339 PMCID: PMC6519032 DOI: 10.1111/mmi.14220] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2019] [Indexed: 12/18/2022]
Abstract
The major facilitator superfamily transporter Rv1410 and the lipoprotein LprG (Rv1411) are encoded by a conserved two-gene operon and contribute to virulence in Mycobacterium tuberculosis. Rv1410 was originally postulated to function as a drug efflux pump, but recent studies suggested that Rv1410 and LprG work in concert to insert triacylglycerides and lipoarabinomannans into the outer membrane. Here, we conducted microscopic analyses of Mycobacterium smegmatis lacking the operon and observed a cell separation defect, while surface rigidity measured by atomic force microscopy was found to be increased. Whereas Rv1410 expressed in Lactococcus lactis did not confer drug resistance, deletion of the operon in Mycobacterium abscessus and M. smegmatis resulted in increased susceptibility toward vancomycin, novobiocin and rifampicin. A homology model of Rv1410 revealed a periplasmic loop as well as a highly conserved aspartate, which were found to be essential for the operon's function. Interestingly, influx of the fluorescent dyes BCECF-AM and calcein-AM in de-energized M. smegmatis cells was faster in the deletion mutant. Our results unambiguously show that elevated drug susceptibility in the deletion mutant is caused by increased drug influx through a defective mycobacterial cell envelope and not by drug efflux mediated by Rv1410.
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Affiliation(s)
- Michael Hohl
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Sille Remm
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Haig A Eskandarian
- Global Health Institute, École polytechnique fédérale de Lausanne, EPFL, Lausanne, Switzerland
| | - Michael Dal Molin
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Fabian M Arnold
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Lea M Hürlimann
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Andri Krügel
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
| | - Georg E Fantner
- Interfaculty Institute for Bioengineering, École polytechnique fédérale de Lausanne, EPFL, Lausanne, Switzerland
| | - Peter Sander
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland.,National Center for Mycobacteria, Zurich, Switzerland
| | - Markus A Seeger
- Institute of Medical Microbiology, University of Zurich, Zürich, Switzerland
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38
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Structural basis for prodrug recognition by the SLC15 family of proton-coupled peptide transporters. Proc Natl Acad Sci U S A 2019; 116:804-809. [PMID: 30602453 PMCID: PMC6338836 DOI: 10.1073/pnas.1813715116] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Poor oral bioavailability is one of the leading causes of compound failure in drug development and a major challenge for the pharmaceutical industry. A successful approach to address this challenge has been the development of prodrugs that target the intestinal peptide transporter, PepT1 (SLC15A1). PepT1 exhibits a remarkably promiscuous binding site and is known to transport many different drug molecules, making it an excellent target for prodrug design and delivery. However, the structural basis for drug recognition remains largely unknown. Here we present the structure of a bacterial homolog of PepT1 bound to both an antiviral prodrug, valacyclovir, and anticancer drug 5-aminolevulinic acid. These structures enable a pharmacophore model to be developed that will aid future prodrug design. A major challenge in drug development is the optimization of intestinal absorption and cellular uptake. A successful strategy has been to develop prodrug molecules, which hijack solute carrier (SLC) transporters for active transport into the body. The proton-coupled oligopeptide transporters, PepT1 and PepT2, have been successfully targeted using this approach. Peptide transporters display a remarkable capacity to recognize a diverse library of di- and tripeptides, making them extremely promiscuous and major contributors to the pharmacokinetic profile of several important drug classes, including beta-lactam antibiotics and antiviral and antineoplastic agents. Of particular interest has been their ability to recognize amino acid and peptide-based prodrug molecules, thereby providing a rational approach to improving drug transport into the body. However, the structural basis for prodrug recognition has remained elusive. Here we present crystal structures of a prokaryotic homolog of the mammalian transporters in complex with the antiviral prodrug valacyclovir and the peptide-based photodynamic therapy agent, 5-aminolevulinic acid. The valacyclovir structure reveals that prodrug recognition is mediated through both the amino acid scaffold and the ester bond, which is commonly used to link drug molecules to the carrier’s physiological ligand, whereas 5-aminolevulinic acid makes far fewer interactions compared with physiological peptides. These structures provide a unique insight into how peptide transporters interact with xenobiotic molecules and provide a template for further prodrug development.
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39
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Sørensen TLM, Hjorth-Jensen SJ, Oksanen E, Andersen JL, Olesen C, Møller JV, Nissen P. Membrane-protein crystals for neutron diffraction. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2018; 74:1208-1218. [PMID: 30605135 DOI: 10.1107/s2059798318012561] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/05/2018] [Indexed: 11/10/2022]
Abstract
Neutron macromolecular crystallography (NMX) has the potential to provide the experimental input to address unresolved aspects of transport mechanisms and protonation in membrane proteins. However, despite this clear scientific motivation, the practical challenges of obtaining crystals that are large enough to make NMX feasible have so far been prohibitive. Here, the potential impact on feasibility of a more powerful neutron source is reviewed and a strategy for obtaining larger crystals is formulated, exemplified by the calcium-transporting ATPase SERCA1. The challenges encountered at the various steps in the process from crystal nucleation and growth to crystal mounting are explored, and it is demonstrated that NMX-compatible membrane-protein crystals can indeed be obtained.
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Affiliation(s)
- Thomas Lykke Møller Sørensen
- Department of Molecular Biology and Genetics - DANDRITE, Aarhus University, Gustav Wieds Vej 10, DK-8000 Aarhus C, Denmark
| | - Samuel John Hjorth-Jensen
- Department of Molecular Biology and Genetics - DANDRITE, Aarhus University, Gustav Wieds Vej 10, DK-8000 Aarhus C, Denmark
| | - Esko Oksanen
- European Spallation Source ERIC, PO Box 176, 22100 Lund, Sweden
| | | | - Claus Olesen
- Department of Biomedicine, Aarhus University, Ole Worn Alle 3, DK-8000 Aarhus C, Denmark
| | - Jesper Vuust Møller
- Department of Biomedicine, Aarhus University, Ole Worn Alle 3, DK-8000 Aarhus C, Denmark
| | - Poul Nissen
- Department of Molecular Biology and Genetics - DANDRITE, Aarhus University, Gustav Wieds Vej 10, DK-8000 Aarhus C, Denmark
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40
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Rojas F, Silvester E, Young J, Milne R, Tettey M, Houston DR, Walkinshaw MD, Pérez-Pi I, Auer M, Denton H, Smith TK, Thompson J, Matthews KR. Oligopeptide Signaling through TbGPR89 Drives Trypanosome Quorum Sensing. Cell 2018; 176:306-317.e16. [PMID: 30503212 PMCID: PMC6333907 DOI: 10.1016/j.cell.2018.10.041] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 09/13/2018] [Accepted: 10/17/2018] [Indexed: 02/03/2023]
Abstract
Trypanosome parasites control their virulence and spread by using quorum sensing (QS) to generate transmissible “stumpy forms” in their host bloodstream. However, the QS signal “stumpy induction factor” (SIF) and its reception mechanism are unknown. Although trypanosomes lack G protein-coupled receptor signaling, we have identified a surface GPR89-family protein that regulates stumpy formation. TbGPR89 is expressed on bloodstream “slender form” trypanosomes, which receive the SIF signal, and when ectopically expressed, TbGPR89 drives stumpy formation in a SIF-pathway-dependent process. Structural modeling of TbGPR89 predicts unexpected similarity to oligopeptide transporters (POT), and when expressed in bacteria, TbGPR89 transports oligopeptides. Conversely, expression of an E. coli POT in trypanosomes drives parasite differentiation, and oligopeptides promote stumpy formation in vitro. Furthermore, the expression of secreted trypanosome oligopeptidases generates a paracrine signal that accelerates stumpy formation in vivo. Peptidase-generated oligopeptide QS signals being received through TbGPR89 provides a mechanism for both trypanosome SIF production and reception. Trypanosomes use quorum sensing to differentiate to transmissible stumpy forms A GPR89 protein with oligopeptide transport activity drives parasite differentiation Oligopeptide mixtures and synthetic di- and tripeptides promote stumpy formation Released parasite oligopeptidases generate the paracrine quorum sensing signal in vivo
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Affiliation(s)
- Federico Rojas
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Eleanor Silvester
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Julie Young
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Rachel Milne
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Mabel Tettey
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK
| | - Douglas R Houston
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Malcolm D Walkinshaw
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Irene Pérez-Pi
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Manfred Auer
- Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Helen Denton
- School of Biology, BSRC, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9ST, UK
| | - Terry K Smith
- School of Biology, BSRC, University of St. Andrews, North Haugh, St. Andrews, Fife KY16 9ST, UK
| | - Joanne Thompson
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK.
| | - Keith R Matthews
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FL, UK.
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41
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Martinez Molledo M, Quistgaard EM, Löw C. Tripeptide binding in a proton-dependent oligopeptide transporter. FEBS Lett 2018; 592:3239-3247. [PMID: 30194725 PMCID: PMC6221056 DOI: 10.1002/1873-3468.13246] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 08/29/2018] [Accepted: 09/05/2018] [Indexed: 01/30/2023]
Abstract
Proton-dependent oligopeptide transporters (POTs) are important for the uptake of di-/tripeptides in many organisms and for drug transport in humans. The binding mode of dipeptides has been well described. However, it is still debated how tripeptides are recognized. Here, we show that tripeptides of the sequence Phe-Ala-Xxx bind with similar affinities as dipeptides to the POT transporter from Streptococcus thermophilus (PepTS t ). We furthermore determined a 2.3-Å structure of PepTS t in complex with Phe-Ala-Gln. The phenylalanine and alanine residues of the peptide adopt the same positions as previously observed for the Phe-Ala dipeptide, while the glutamine side chain extends into a hitherto uncharacterized pocket. This pocket is adaptable in size and can likely accommodate a wide variety of peptide side chains.
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Affiliation(s)
- Maria Martinez Molledo
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Hamburg, Germany
| | - Esben M Quistgaard
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Hamburg, Germany.,Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Hamburg, Germany.,Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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42
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Migocka M, Małas K, Maciaszczyk-Dziubinska E, Papierniak A, Posyniak E, Garbiec A. Cucumber metal tolerance protein 7 (CsMTP7) is involved in the accumulation of Fe in mitochondria under Fe excess. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:988-1003. [PMID: 29932267 DOI: 10.1111/tpj.14006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Revised: 06/04/2018] [Accepted: 06/14/2018] [Indexed: 06/08/2023]
Abstract
The plant metal tolerance protein family (MTP) includes 12 members that have been classified into three phylogenetically different subgroups - Zn-cation diffusion facilitator (CDF), Fe/Zn-CDF and Mn-CDF - based on their putative metal specificity. To date, only members belonging to the Zn-CDF or Mn-CDF group have been characterized functionally. The plant Fe/Zn-CDF subgroup includes two proteins, MTP6 and MTP7, but their function and metal specificity have not been confirmed. In this study we showed that cucumber CsMTP7 is a highly specific mitochondrial Fe importer that is able to confer yeast tolerance to Fe excess through increased accumulation of Fe in the mitochondria. We also demonstrated that CsMTP7 contributes to the increased accumulation of Fe in the mitochondria of Arabidopsis thaliana protoplasts. The transcripts and mitochondrial levels of CsMTP7 and ferritin - the iron-storing protein - are significantly increased in cucumber roots in response to Fe excess. This finding suggests that CsMTP7 and ferritin work in concert to accumulate Fe in plant mitochondria. As genes that encode orthologous proteins have been identified in phylogenetically distant organisms, including Archaea, cyanobacteria, humans and plants, but not in yeast, we concluded that the MTP7-mediated mitochondrial Fe accumulation may be conserved in the species, and express mitochondrial ferritin for mitochondrial Fe storage.
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Affiliation(s)
- Magdalena Migocka
- Department of Plant Molecular Physiology, Institute of Experimental Biology, Wroclaw University, Kanonia 6/8, 50-328, Wroclaw, Poland
| | - Karolina Małas
- Department of Plant Molecular Physiology, Institute of Experimental Biology, Wroclaw University, Kanonia 6/8, 50-328, Wroclaw, Poland
| | - Ewa Maciaszczyk-Dziubinska
- Department of Genetics and Cell Physiology, Institute of Experimental Biology, Wroclaw University, Kanonia 6/8, 50-328, Wroclaw, Poland
| | - Anna Papierniak
- Department of Plant Molecular Physiology, Institute of Experimental Biology, Wroclaw University, Kanonia 6/8, 50-328, Wroclaw, Poland
| | - Ewelina Posyniak
- Department of Animal Developmental Biology, Institute of Experimental Biology, Wroclaw University, Sienkiewicza 21, 50-335, Wroclaw, Poland
| | - Arnold Garbiec
- Department of Animal Developmental Biology, Institute of Experimental Biology, Wroclaw University, Sienkiewicza 21, 50-335, Wroclaw, Poland
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43
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Wang B, Xie N, Li B. Influence of peptide characteristics on their stability, intestinal transport, and in vitro bioavailability: A review. J Food Biochem 2018; 43:e12571. [PMID: 31353489 DOI: 10.1111/jfbc.12571] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 01/30/2018] [Accepted: 03/02/2018] [Indexed: 11/29/2022]
Abstract
In recent years, large amounts of peptides have been purified and characterized from food protein hydrolysates. Many of these peptides have been demonstrated to be of potential application as health-improving ingredients against plenty of disease conditions, such as cancer, inflammation, and cardiovascular disease. The real efficacy of functional application of these peptides depends on their stability, transport, and bioavailability in target tissues, which in turn depends on the peptides characteristics. Therefore, the characteristic-function parameters are crucial for peptides using as functional agents. This review article intends to summarize the effects of peptide characteristics, including molecular weight, charge and hydrophobicity, on their stability, intestinal transport, and in vitro bioavailability. PRACTICAL APPLICATIONS: In the near future, bioactive peptides will play important roles in the area of functional foods and pharmacy. However, the gastrointestinal digestion and transport usually restrict their bioavailability in vivo. Understanding the relationships between peptide characteristics and their digestion stability, bioavailability may provide guidance and theoretical basis for the further application of bioactive peptides.
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Affiliation(s)
- Bo Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.,School of Food Science and Engineering, South China University of Technology, Guangzhou, China.,South China Institute of Collaborative Innovation, Dongguan, China
| | - Ningning Xie
- Institute of Agro-Products Processing, Research of Anhui Academy of Agricultural Sciences, Hefei, China
| | - Bo Li
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.,Key Laboratory of Functional Dairy, Ministry of Education, Beijing, China
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44
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Minhas GS, Bawdon D, Herman R, Rudden M, Stone AP, James AG, Thomas GH, Newstead S. Structural basis of malodour precursor transport in the human axilla. eLife 2018; 7:e34995. [PMID: 29966586 PMCID: PMC6059767 DOI: 10.7554/elife.34995] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 06/23/2018] [Indexed: 01/10/2023] Open
Abstract
Mammals produce volatile odours that convey different types of societal information. In Homo sapiens, this is now recognised as body odour, a key chemical component of which is the sulphurous thioalcohol, 3-methyl-3-sulfanylhexan-1-ol (3M3SH). Volatile 3M3SH is produced in the underarm as a result of specific microbial activity, which act on the odourless dipeptide-containing malodour precursor molecule, S-Cys-Gly-3M3SH, secreted in the axilla (underarm) during colonisation. The mechanism by which these bacteria recognise S-Cys-Gly-3M3SH and produce body odour is still poorly understood. Here we report the structural and biochemical basis of bacterial transport of S-Cys-Gly-3M3SH by Staphylococcus hominis, which is converted to the sulphurous thioalcohol component 3M3SH in the bacterial cytoplasm, before being released into the environment. Knowledge of the molecular basis of precursor transport, essential for body odour formation, provides a novel opportunity to design specific inhibitors of malodour production in humans.
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Affiliation(s)
- Gurdeep S Minhas
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
| | - Daniel Bawdon
- Department of BiologyUniversity of YorkYorkUnited Kingdom
| | - Reyme Herman
- Department of BiologyUniversity of YorkYorkUnited Kingdom
| | | | - Andrew P Stone
- Department of BiologyUniversity of YorkYorkUnited Kingdom
| | | | - Gavin H Thomas
- Department of BiologyUniversity of YorkYorkUnited Kingdom
| | - Simon Newstead
- Department of BiochemistryUniversity of OxfordOxfordUnited Kingdom
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45
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Abele R, Tampé R. Moving the Cellular Peptidome by Transporters. Front Cell Dev Biol 2018; 6:43. [PMID: 29761100 PMCID: PMC5937356 DOI: 10.3389/fcell.2018.00043] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 04/03/2018] [Indexed: 12/18/2022] Open
Abstract
Living matter is defined by metastability, implying a tightly balanced synthesis and turnover of cellular components. The first step of eukaryotic protein degradation via the ubiquitin-proteasome system (UPS) leads to peptides, which are subsequently degraded to single amino acids by an armada of proteases. A small fraction of peptides, however, escapes further cytosolic destruction and is transported by ATP-binding cassette (ABC) transporters into the endoplasmic reticulum (ER) and lysosomes. The ER-resident heterodimeric transporter associated with antigen processing (TAP) is a crucial component in adaptive immunity for the transport and loading of peptides onto major histocompatibility complex class I (MHC I) molecules. Although the function of the lysosomal resident homodimeric TAPL-like (TAPL) remains, until today, only loosely defined, an involvement in immune defense is anticipated since it is highly expressed in dendritic cells and macrophages. Here, we compare the gene organization and the function of single domains of both peptide transporters. We highlight the structural organization, the modes of substrate binding and translocation as well as physiological functions of both organellar transporters.
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Affiliation(s)
- Rupert Abele
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt, Germany
| | - Robert Tampé
- Institute of Biochemistry, Biocenter, Goethe University Frankfurt, Frankfurt, Germany.,Cluster of Excellence - Macromolecular Complexes, Goethe University Frankfurt, Frankfurt, Germany
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46
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Yaffe D, Forrest LR, Schuldiner S. The ins and outs of vesicular monoamine transporters. J Gen Physiol 2018; 150:671-682. [PMID: 29666153 PMCID: PMC5940252 DOI: 10.1085/jgp.201711980] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 03/26/2018] [Indexed: 01/31/2023] Open
Abstract
Yaffe et al. review structure-guided studies that have provided insight into the mechanism of proton-monoamine antiport by VMATs. The H+-coupled vesicular monoamine transporter (VMAT) is a transporter essential for life. VMAT mediates packaging of the monoamines serotonin, dopamine, norepinephrine, and histamine from the neuronal cytoplasm into presynaptic vesicles, which is a key step in the regulated release of neurotransmitters. However, a detailed understanding of the mechanism of VMAT function has been limited by the lack of availability of high-resolution structural data. In recent years, a series of studies guided by homology models has revealed significant insights into VMAT function, identifying residues that contribute to the binding site and to specific steps in the transport cycle. Moreover, to characterize the conformational transitions that occur upon binding of the substrate and coupling ion, we have taken advantage of the unique and powerful pharmacology of VMAT as well as of mutants that affect the conformational equilibrium of the protein and shift it toward defined conformations. This has allowed us to identify an important role for the proton gradient in driving a shift from lumen-facing to cytoplasm-facing conformations.
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Affiliation(s)
- Dana Yaffe
- Department of Biological Chemistry, Alexander Silberman Institute of Life Sciences, Hebrew University, Jerusalem, Israel
| | - Lucy R Forrest
- Computational Structural Biology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD
| | - Shimon Schuldiner
- Department of Biological Chemistry, Alexander Silberman Institute of Life Sciences, Hebrew University, Jerusalem, Israel
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47
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Viennois E, Pujada A, Zen J, Merlin D. Function, Regulation, and Pathophysiological Relevance of the POT Superfamily, Specifically PepT1 in Inflammatory Bowel Disease. Compr Physiol 2018; 8:731-760. [PMID: 29687900 DOI: 10.1002/cphy.c170032] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Mammalian members of the proton-coupled oligopeptide transporter family are integral membrane proteins that mediate the cellular uptake of di/tripeptides and peptide-like drugs and couple substrate translocation to the movement of H+ , with the transmembrane electrochemical proton gradient providing the driving force. Peptide transporters are responsible for the (re)absorption of dietary and/or bacterial di- and tripeptides in the intestine and kidney and maintaining homeostasis of neuropeptides in the brain. These proteins additionally contribute to absorption of a number of pharmacologically important compounds. In this overview article, we have provided updated information on the structure, function, expression, localization, and activities of PepT1 (SLC15A1), PepT2 (SLC15A2), PhT1 (SLC15A4), and PhT2 (SLC15A3). Peptide transporters, in particular, PepT1 are discussed as drug-delivery systems in addition to their implications in health and disease. Particular emphasis has been placed on the involvement of PepT1 in the physiopathology of the gastrointestinal tract, specifically, its role in inflammatory bowel diseases. © 2018 American Physiological Society. Compr Physiol 8:731-760, 2018.
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Affiliation(s)
- Emilie Viennois
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Adani Pujada
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Jane Zen
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA
| | - Didier Merlin
- Institute for Biomedical Sciences, Center for Diagnostics and Therapeutics, Georgia State University, Atlanta, Georgia, USA.,Veterans Affairs Medical Center, Decatur, Georgia, USA
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48
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Multispecific Substrate Recognition in a Proton-Dependent Oligopeptide Transporter. Structure 2018; 26:467-476.e4. [PMID: 29429879 PMCID: PMC5845931 DOI: 10.1016/j.str.2018.01.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/22/2017] [Accepted: 01/10/2018] [Indexed: 12/27/2022]
Abstract
Proton-dependent oligopeptide transporters (POTs) are important for uptake of dietary di- and tripeptides in many organisms, and in humans are also involved in drug absorption. These transporters accept a wide range of substrates, but the structural basis for how different peptide side chains are accommodated has so far remained obscure. Twenty-eight peptides were screened for binding to PepTSt from Streptococcus thermophilus, and structures were determined of PepTSt in complex with four physicochemically diverse dipeptides, which bind with millimolar affinity: Ala-Leu, Phe-Ala, Ala-Gln, and Asp-Glu. The structures show that PepTSt can adapt to different peptide side chains through movement of binding site residues and water molecules, and that a good fit can be further aided by adjustment of the position of the peptide itself. Finally, structures were also determined in complex with adventitiously bound HEPES, polyethylene glycol, and phosphate molecules, which further underline the adaptability of the binding site. Dipeptides can adapt their position to best fit the PepTSt binding site The PepTSt binding site can adapt its structure to best fit the dipeptides The water network in the PepTSt binding site can adapt to best fit the dipeptides Aromatic binding site residues play a role in conferring PepTSt multispecificity
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49
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Longo A, Miles NW, Dickstein R. Genome Mining of Plant NPFs Reveals Varying Conservation of Signature Motifs Associated With the Mechanism of Transport. FRONTIERS IN PLANT SCIENCE 2018; 9:1668. [PMID: 30564251 PMCID: PMC6288477 DOI: 10.3389/fpls.2018.01668] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/26/2018] [Indexed: 05/04/2023]
Abstract
Nitrogen is essential for all living species and may be taken up from the environment in different forms like nitrate or peptides. In plants, members of a transporter family named NPFs transport nitrate and peptides across biological membranes. NPFs are phylogenetically related to a family of peptide transporters (PTRs) or proton-coupled oligopeptide transporters (POTs) that are evolutionarily conserved in all organisms except in Archaea. POTs are present in low numbers in bacteria, algae and animals. NPFs have expanded in plants and evolved to transport a wide range of substrates including phytohormones and glucosinolates. Functional studies have shown that most NPFs, like POTs, operate as symporters with simultaneous inwardly directed movement of protons. Here we focus on four structural features of NPFs/POTs/PTRs that have been shown by structural and functional studies to be essential to proton-coupled symport transport. The first two features are implicated in proton binding and transport: a conserved motif named ExxER/K, located in the first transmembrane helix (TMH1) and a D/E residue in TMH7 that has been observed in some bacterial and algal transporters. The third and fourth features are two inter-helical salt bridges between residues on TMH1 and TMH7 or TMH4 and TMH10. To understand if the mechanism of transport is conserved in NPFs with the expansion to novel substrates, we collected NPFs sequences from 42 plant genomes. Sequence alignment revealed that the ExxER/K motif is not strictly conserved and its conservation level is different in the NPF subfamilies. The proton binding site on TMH7 is missing in all NPFs with the exception of two NPFs from moss. The two moss NPFs also have a positively charged amino acid on TMH1 that can form the salt bridge with the TMH7 negative residue. None of the other NPFs we examined harbor residues that can form the TMH1-TMH7 salt bridge. In contrast, the amino acids required to form the TMH4-TMH10 salt bridge are highly conserved in NPFs, with some exceptions. These results support the need for further biochemical and structural studies of individual NPFs for a better understanding of the transport mechanism in this family of transporters.
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Affiliation(s)
- Antonella Longo
- BioDiscovery Institute, University of North Texas, Denton, TX, United States
- Department of Biological Sciences, University of North Texas, Denton, TX, United States
- *Correspondence: Antonella Longo,
| | - Nicholas W. Miles
- BioDiscovery Institute, University of North Texas, Denton, TX, United States
- Department of Biological Sciences, University of North Texas, Denton, TX, United States
| | - Rebecca Dickstein
- BioDiscovery Institute, University of North Texas, Denton, TX, United States
- Department of Biological Sciences, University of North Texas, Denton, TX, United States
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Wang CY, Liu S, Xie XN, Tan ZR. Regulation profile of the intestinal peptide transporter 1 (PepT1). DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:3511-3517. [PMID: 29263649 PMCID: PMC5726373 DOI: 10.2147/dddt.s151725] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The intestinal peptide transporter 1 (PepT1) was first identified in 1994. It plays a crucial role in the absorption of small peptides including not only >400 different dipeptides and 8,000 tripeptides digested from dietary proteins but also a repertoire of structurally related compounds and drugs. Owing to its critical role in the bioavailability of peptide-like drugs, such as the anti-cancer agents and anti-virus drug, PepT1 is increasingly becoming a striking prodrug-designing target. Therefore, the understanding of PepT1 gene regulation is of great importance both for dietary adaptation and for clinical drug treatment. After decades of research, it has been recognized that PepT1 could be regulated at the transcriptional and post-transcriptional levels by numerous factors. Therefore, the present review intends to summarize the progress made in the regulation of PepT1 and provide insights into the PepT1's potential in clinical aspects of nutritional and drug therapies.
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Affiliation(s)
- Chun-Yang Wang
- Department of Clinical Pharmacology, Xiangya Hospital, Xiangya School of Medicine, Central South University.,Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, People's Republic of China
| | - Shu Liu
- Department of Clinical Pharmacology, Xiangya Hospital, Xiangya School of Medicine, Central South University.,Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, People's Republic of China
| | - Xiao-Nv Xie
- Department of Clinical Pharmacology, Xiangya Hospital, Xiangya School of Medicine, Central South University.,Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, People's Republic of China
| | - Zhi-Rong Tan
- Department of Clinical Pharmacology, Xiangya Hospital, Xiangya School of Medicine, Central South University.,Hunan Key Laboratory of Pharmacogenetics, Institute of Clinical Pharmacology, Central South University, Changsha, Hunan, People's Republic of China
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