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Cao Y, Song W, Chen X. Multivalent sialic acid materials for biomedical applications. Biomater Sci 2023; 11:2620-2638. [PMID: 36661319 DOI: 10.1039/d2bm01595a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Sialic acid is a kind of monosaccharide expressed on the non-reducing end of glycoproteins or glycolipids. It acts as a signal molecule combining with its natural receptors such as selectins and siglecs (sialic acid-binding immunoglobulin-like lectins) in intercellular interactions like immunological surveillance and leukocyte infiltration. The last few decades have witnessed the exploration of the roles that sialic acid plays in different physiological and pathological processes and the use of sialic acid-modified materials as therapeutics for related diseases like immune dysregulation and virus infection. In this review, we will briefly introduce the biomedical function of sialic acids in organisms and the utilization of multivalent sialic acid materials for targeted drug delivery as well as therapeutic applications including anti-inflammation and anti-virus.
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Affiliation(s)
- Yusong Cao
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China
| | - Wantong Song
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China.,Jilin Biomedical Polymers Engineering Laboratory, Changchun, 130022, China
| | - Xuesi Chen
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. .,University of Science and Technology of China, Hefei, 230026, China.,Jilin Biomedical Polymers Engineering Laboratory, Changchun, 130022, China
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2
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Thalji MR, Ibrahim AA, Chong KF, Soldatov AV, Ali GAM. Glycopolymer-Based Materials: Synthesis, Properties, and Biosensing Applications. Top Curr Chem (Cham) 2022; 380:45. [PMID: 35951265 PMCID: PMC9366760 DOI: 10.1007/s41061-022-00395-5] [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: 03/01/2022] [Accepted: 06/02/2022] [Indexed: 11/30/2022]
Abstract
Glycopolymer materials have emerged as a significant biopolymer class that has piqued the scientific community's attention due to their potential applications. Recently, they have been found to be a unique synthetic biomaterial; glycopolymer materials have also been used for various applications, including direct therapeutic methods, medical adhesives, drug/gene delivery systems, and biosensor applications. Therefore, for the next stage of biomaterial research, it is essential to understand current breakthroughs in glycopolymer-based materials research. This review discusses the most widely utilized synthetic methodologies for glycopolymer-based materials, their properties based on structure–function interactions, and the significance of these materials in biosensing applications, among other topics. When creating glycopolymer materials, contemporary polymerization methods allow precise control over molecular weight, molecular weight distribution, chemical activity, and polymer architecture. This review concludes with a discussion of the challenges and complexities of glycopolymer-based biosensors, in addition to their potential applications in the future.
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Affiliation(s)
- Mohammad R Thalji
- School of Chemical Engineering, Yeungnam University, Gyeongsan, 38541, Gyeongbuk, South Korea
| | - Amal Amin Ibrahim
- Polymers and pigments department, Chemical industries research institute, National Research Centre, El-Bohouth St, Dokki, Cairo, 12622, Egypt
| | - Kwok Feng Chong
- Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Gambang, 26300, Kuantan, Malaysia
| | - Alexander V Soldatov
- The Smart Materials Research Institute, Southern Federal University, Sladkova Str. 178/24, Rostov-on-Don, Russian Federation
| | - Gomaa A M Ali
- Chemistry Department, Faculty of Science, Al-Azhar University, Assiut, 71524, Egypt.
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3
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Characterization of opposing responses to phenol by Bacillus subtilis chemoreceptors. J Bacteriol 2022; 204:e0044121. [PMID: 35007157 DOI: 10.1128/jb.00441-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacillus subtilis employs ten chemoreceptors to move in response to chemicals in its environment. While the sensing mechanisms have been determined for many attractants, little is known about the sensing mechanisms for repellents. In this work, we investigated phenol chemotaxis in B. subtilis. Phenol is an attractant at low, micromolar concentrations, and a repellent at high, millimolar concentrations. McpA was found to be the principal chemoreceptor governing the repellent response to phenol and other related aromatic compounds. In addition, the chemoreceptors McpC and HemAT were found to govern the attractant response to phenol and related compounds. Using chemoreceptor chimeras, McpA was found to sense phenol using its signaling domain rather than its sensing domain. These observations were substantiated in vitro, where direct binding of phenol to the signaling domain of McpA was observed using saturation-transfer difference nuclear magnetic resonance. These results further advance our understanding of B. subtilis chemotaxis and further demonstrate that the signaling domain of B. subtilis chemoreceptors can directly sense chemoeffectors. IMPORTANCE Bacterial chemotaxis is commonly thought to employ a sensing mechanism involving the extracellular sensing domain of chemoreceptors. Some ligands, however, appear to be sensed by the signaling domain. Phenolic compounds, commonly found in soil and root exudates, provide environmental cues for soil microbes like Bacillus subtilis. We show that phenol is sensed both as an attractant and a repellent. While the mechanism for sensing phenol as an attractant is still unknown, we found that phenol is sensed as a repellent by the signaling domain of the chemoreceptor McpA. This study furthers our understanding of the unconventional sensing mechanisms employed by the B. subtilis chemotaxis pathway.
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4
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Critical parameters for design and development of multivalent nanoconstructs: recent trends. Drug Deliv Transl Res 2022; 12:2335-2358. [PMID: 35013982 PMCID: PMC8747862 DOI: 10.1007/s13346-021-01103-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2021] [Indexed: 12/16/2022]
Abstract
A century ago, the groundbreaking concept of the magic bullet was given by Paul Ehrlich. Since then, this concept has been extensively explored in various forms to date. The concept of multivalency is among such advancements of the magic bullet concept. Biologically, the concept of multivalency plays a critical role in significantly huge numbers of biochemical interactions. This concept is the sole reason behind the higher affinity of biological molecules like viruses to more selectively target the host cell surface receptors. Multivalent nanoconstructs are a promising approach for drug delivery by the active targeting principle. Designing and developing effective and target-specific multivalent drug delivery nanoconstructs, on the other hand, remain a challenge. The underlying reason for this is a lack of understanding of the crucial interactions between ligands and cell surface receptors, as well as the design of nanoconstructs. This review highlights the need for a better theoretical understanding of the multivalent effect of what happens to the receptor-ligand complex after it has been established. Furthermore, the critical parameters for designing and developing robust multivalent systems have been emphasized. We have also discussed current advances in the design and development of multivalent nanoconstructs for drug delivery. We believe that a thorough knowledge of theoretical concepts and experimental methodologies may transform a brilliant idea into clinical translation.
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5
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Zhao H, Yin CC, Ma B, Chen SY, Zhang JS. Ethylene signaling in rice and Arabidopsis: New regulators and mechanisms. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2021; 63:102-125. [PMID: 33095478 DOI: 10.1111/jipb.13028] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/21/2020] [Indexed: 05/22/2023]
Abstract
Ethylene is a gaseous hormone which plays important roles in both plant growth and development and stress responses. Based on studies in the dicot model plant species Arabidopsis, a linear ethylene signaling pathway has been established, according to which ethylene is perceived by ethylene receptors and transduced through CONSTITUTIVE TRIPLE RESPONSE 1 (CTR1) and ETHYLENE-INSENSITIVE 2 (EIN2) to activate transcriptional reprogramming. In addition to this canonical signaling pathway, an alternative ethylene receptor-mediated phosphor-relay pathway has also been proposed to participate in ethylene signaling. In contrast to Arabidopsis, rice, a monocot, grows in semiaquatic environments and has a distinct plant structure. Several novel regulators and/or mechanisms of the rice ethylene signaling pathway have recently been identified, indicating that the ethylene signaling pathway in rice has its own unique features. In this review, we summarize the latest progress and compare the conserved and divergent aspects of the ethylene signaling pathway between Arabidopsis and rice. The crosstalk between ethylene and other plant hormones is also reviewed. Finally, we discuss how ethylene regulates plant growth, stress responses and agronomic traits. These analyses should help expand our knowledge of the ethylene signaling mechanism and could further be applied for agricultural purposes.
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Affiliation(s)
- He Zhao
- State Key Lab of Plant Genomics, Institute of Genetics & Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
| | - Cui-Cui Yin
- State Key Lab of Plant Genomics, Institute of Genetics & Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
| | - Biao Ma
- Biology and Agriculture Research Center, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100024, China
| | - Shou-Yi Chen
- State Key Lab of Plant Genomics, Institute of Genetics & Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
| | - Jin-Song Zhang
- State Key Lab of Plant Genomics, Institute of Genetics & Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
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6
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Zhou X, Zhao M, Liu Y, Chen Q, Shen L. Statistical Binding Matching between Influenza A Virus and Dynamic Glycan Clusters Determines Its Adhesion onto Lipid Membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:15212-15219. [PMID: 33307709 DOI: 10.1021/acs.langmuir.0c02047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The resistance of drugs to the new influenza A virus (IAV) strains and the limited efficiency of vaccines to prevent seasonal flu epidemics underscore the urgency in finding novel strategies to block IAV infection, which is required to gain insights into the mechanism of the initial step of IAV adhesion. While it is well established that IAVs bind to respiratory tract cells by recognizing sialylated glycans on host cell membranes through a multivalency effect, how IAVs dynamically respond to multiple glycan receptors via distinct valencies has not been fully understood, limiting the discovery of novel anti-flu strategies. Using single-particle tracking to record the 2D mobilities and surface residence times of highly pathogenic H5N1 avian IAVs adhered to fluidic membranes containing α2-3 sialylated GM3 glycolipids, we quantified the univalent and multivalent IAV adhesion channels, which provide insights into the mechanism of IAV binding; IAV can guide the clustering of dynamic glycolipids to statistically match the multivalent binding affinities for IAV adhesion. This mechanism can be inhibited by disrupting the dynamic glycan clustering on membranes of varying fluidities, like the gel phase membrane. This work facilitates a deeper fundamental understanding of IAV infection as well as the development of novel anti-flu strategies.
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Affiliation(s)
- Xin Zhou
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Min Zhao
- School of Basic Medical Sciences, Hubei University of Chinese Medicine, Wuhan 430065, China
| | - Yuanyuan Liu
- School of Basic Medical Sciences, Institute of Medical Virology, Wuhan University, Wuhan 430071, China
| | - Quanjiao Chen
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Lei Shen
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
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7
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Xu Y, Zhang H, Liu XW. Antimicrobial Carbohydrate-Based Macromolecules: Their Structures and Activities. J Org Chem 2020; 85:15827-15836. [DOI: 10.1021/acs.joc.0c01597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Yuan Xu
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Hongbin Zhang
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education and Yunnan Province, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Xue-Wei Liu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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8
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Miura Y. Controlled polymerization for the development of bioconjugate polymers and materials. J Mater Chem B 2020; 8:2010-2019. [DOI: 10.1039/c9tb02418b] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conjugates of various biopolymers with synthetic polymers were preparedvialiving radical polymerization. The conjugates have precise structures and potential for novel biofunctional materials.
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Affiliation(s)
- Yoshiko Miura
- Department of Chemical Engineering
- Graduate School of Engineering
- Kyushu University
- Fukuoka 819-0395
- Japan
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9
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Vacchini M, Edwards R, Guizzardi R, Palmioli A, Ciaramelli C, Paiotta A, Airoldi C, La Ferla B, Cipolla L. Glycan Carriers As Glycotools for Medicinal Chemistry Applications. Curr Med Chem 2019; 26:6349-6398. [DOI: 10.2174/0929867326666190104164653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 11/07/2018] [Accepted: 12/18/2018] [Indexed: 12/12/2022]
Abstract
Carbohydrates are one of the most powerful and versatile classes of biomolecules that nature
uses to regulate organisms’ biochemistry, modulating plenty of signaling events within cells, triggering
a plethora of physiological and pathological cellular behaviors. In this framework, glycan carrier
systems or carbohydrate-decorated materials constitute interesting and relevant tools for medicinal
chemistry applications. In the last few decades, efforts have been focused, among others, on the development
of multivalent glycoconjugates, biosensors, glycoarrays, carbohydrate-decorated biomaterials
for regenerative medicine, and glyconanoparticles. This review aims to provide the reader with a general
overview of the different carbohydrate carrier systems that have been developed as tools in different
medicinal chemistry approaches relying on carbohydrate-protein interactions. Given the extent of
this topic, the present review will focus on selected examples that highlight the advancements and potentialities
offered by this specific area of research, rather than being an exhaustive literature survey of
any specific glyco-functionalized system.
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Affiliation(s)
- Mattia Vacchini
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Rana Edwards
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Roberto Guizzardi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Alessandro Palmioli
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Carlotta Ciaramelli
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Alice Paiotta
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Cristina Airoldi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Barbara La Ferla
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
| | - Laura Cipolla
- Department of Biotechnology and Biosciences, University of Milano-Bicocca Milano, Italy
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10
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Ringgaard S, Yang W, Alvarado A, Schirner K, Briegel A. Chemotaxis arrays in Vibrio species and their intracellular positioning by the ParC/ParP system. J Bacteriol 2018; 200:e00793-17. [PMID: 29531180 PMCID: PMC6040185 DOI: 10.1128/jb.00793-17] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Most motile bacteria are able to bias their movement towards more favorable environments or to escape from obnoxious substances by a process called chemotaxis. Chemotaxis depends on a chemosensory system that is able to sense specific environmental signals and generate a behavioral response. Typically, the signal is transmitted to the bacterial flagellum, ultimately regulating the swimming behavior of individual cells. Chemotaxis is mediated by proteins that assemble into large, highly ordered arrays. It is imperative for successful chemotactic behavior and cellular competitiveness that chemosensory arrays form and localize properly within the cell. Here we review how chemotaxis arrays form and localize in Vibrio cholerae and Vibrio parahaemolyticus We focus on how the ParC/ParP-system mediates cell cycle-dependent polar localization of chemotaxis arrays and thus ensures proper cell pole development and array inheritance upon cell division.
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Affiliation(s)
- Simon Ringgaard
- Departmet of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany.
| | - Wen Yang
- Institute of Biology, Leiden University, Leiden, Netherlands
| | - Alejandra Alvarado
- Departmet of Ecophysiology, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | | | - Ariane Briegel
- Institute of Biology, Leiden University, Leiden, Netherlands
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11
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Pollard AM, Sourjik V. Transmembrane region of bacterial chemoreceptor is capable of promoting protein clustering. J Biol Chem 2017; 293:2149-2158. [PMID: 29259129 DOI: 10.1074/jbc.m117.796722] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 12/06/2017] [Indexed: 11/06/2022] Open
Abstract
Many membrane proteins are known to form higher-order oligomers, but the degree to which membrane regions could facilitate protein complex assembly remains largely unclear. Clusters of chemotaxis receptors are among the most prominent structures in the bacterial cell membrane, and they play important functions in processing of chemotactic signals. Although much work has been done to elucidate mechanisms of cluster formation, it almost exclusively focused on cytoplasmic interactions among receptors and other chemotaxis proteins, whereas involvement of membrane-mediated interactions was only hypothesized. Here we used imaging of constructs composed of only a fluorescent protein and the TM helices of Tar to demonstrate that interactions between the lipid bilayer and transmembrane (TM) helices of Escherichia coli chemoreceptors alone are sufficient to mediate clustering. We found that the ability to cluster depends on the sequence or length of the TM helices, implying that certain conformations of these helices facilitate clustering, whereas others do not. Notably, observed sequence specificity was apparently consistent with differences in clustering between native E. coli receptors, with the TM sequence of better-clustering high-abundance receptors being more efficient in promoting membrane-mediated complex formation. These results indicate that being more than just membrane anchors, TM helices could play an important role in the clustering and organization of membrane proteins in bacteria.
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Affiliation(s)
- Abiola M Pollard
- From the Max Planck Institute for Terrestrial Microbiology and LOEWE Center for Synthetic Microbiology (SYNMIKRO), D-35043 Marburg, Germany
| | - Victor Sourjik
- From the Max Planck Institute for Terrestrial Microbiology and LOEWE Center for Synthetic Microbiology (SYNMIKRO), D-35043 Marburg, Germany
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12
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Abstract
Fertilization is exceptionally complex and, depending on the species, happens in entirely different environments. External fertilizers in aquatic habitats, like marine invertebrates or fish, release their gametes into the seawater or freshwater, whereas sperm from most internal fertilizers like mammals cross the female genital tract to make their way to the egg. Various chemical and physical cues guide sperm to the egg. Quite generally, these cues enable signaling pathways that ultimately evoke a cellular Ca2+ response that modulates the waveform of the flagellar beat and, hence, the swimming path. To cope with the panoply of challenges to reach and fertilize the egg, sperm from different species have developed their own unique repertoire of signaling molecules and mechanisms. Here, we review the differences and commonalities for sperm sensory signaling in marine invertebrates (sea urchin), fish (zebrafish), and mammals (mouse, human).
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Affiliation(s)
- Dagmar Wachten
- Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
| | - Jan F Jikeli
- Minerva Max Planck Research Group, Molecular Physiology, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
| | - U Benjamin Kaupp
- Department Molecular Sensory Systems, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
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13
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Magennis EP, Francini N, Mastrotto F, Catania R, Redhead M, Fernandez-Trillo F, Bradshaw D, Churchley D, Winzer K, Alexander C, Mantovani G. Polymers for binding of the gram-positive oral pathogen Streptococcus mutans. PLoS One 2017; 12:e0180087. [PMID: 28672031 PMCID: PMC5495209 DOI: 10.1371/journal.pone.0180087] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 06/09/2017] [Indexed: 01/08/2023] Open
Abstract
Streptococcus mutans is the most significant pathogenic bacterium implicated in the formation of dental caries and, both directly and indirectly, has been associated with severe conditions such as multiple sclerosis, cerebrovascular and peripheral artery disease. Polymers able to selectively bind S. mutans and/or inhibit its adhesion to oral tissue in a non-lethal manner would offer possibilities for addressing pathogenicity without selecting for populations resistant against bactericidal agents. In the present work two libraries of 2-(dimethylamino)ethyl methacrylate (pDMAEMA)-based polymers were synthesized with various proportions of either N,N,N-trimethylethanaminium cationic- or sulfobetaine zwitterionic groups. These copolymers where initially tested as potential macromolecular ligands for S. mutans NCTC 10449, whilst Escherichia coli MG1655 was used as Gram-negative control bacteria. pDMAEMA-derived materials with high proportions of zwitterionic repeating units were found to be selective for S. mutans, in both isolated and S. mutans-E. coli mixed bacterial cultures. Fully sulfobetainized pDMAEMA was subsequently found to bind/cluster preferentially Gram-positive S. mutans and S. aureus compared to Gram negative E. coli and V. harveyi. A key initial stage of S. mutans pathogenesis involves a lectin-mediated adhesion to the tooth surface, thus the range of potential macromolecular ligands was further expanded by investigating two glycopolymers bearing α-mannopyranoside and β-galactopyranoside pendant units. Results with these polymers indicated that preferential binding to either S. mutans or E. coli can be obtained by modulating the glycosylation pattern of the chosen multivalent ligands without incurring unacceptable cytotoxicity in a model gastrointestinal cell line. Overall, our results allowed to identify a structure-property relationship for the potential antimicrobial polymers investigated, and suggest that preferential binding to Gram-positive S. mutans could be achieved by fine-tuning of the recognition elements in the polymer ligands.
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Affiliation(s)
- Eugene P. Magennis
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | - Nora Francini
- School of Medicine, University of Nottingham, Nottingham, United Kingdom
| | - Francesca Mastrotto
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
- Department of Pharmaceutical and Pharmacological Science, University of Padova, Padova, Italy
| | - Rosa Catania
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | - Martin Redhead
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | | | - David Bradshaw
- GlaxoSmithKline, St Georges Avenue, Weybridge, Surrey, United Kingdom
| | - David Churchley
- GlaxoSmithKline, St Georges Avenue, Weybridge, Surrey, United Kingdom
| | - Klaus Winzer
- BBSRC/EPSRC Synthetic Biology Research Centre (SBRC), School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Cameron Alexander
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
| | - Giuseppe Mantovani
- School of Pharmacy, University of Nottingham, Nottingham, United Kingdom
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14
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Briegel A, Jensen G. Progress and Potential of Electron Cryotomography as Illustrated by Its Application to Bacterial Chemoreceptor Arrays. Annu Rev Biophys 2017; 46:1-21. [PMID: 28301773 DOI: 10.1146/annurev-biophys-070816-033555] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Electron cryotomography (ECT) can produce three-dimensional images of biological samples such as intact cells in a near-native, frozen-hydrated state to macromolecular resolution (∼4 nm). Because one of its first and most common applications has been to bacterial chemoreceptor arrays, ECT's contributions to this field illustrate well its past, present, and future. While X-ray crystallography and nuclear magnetic resonance spectroscopy have revealed the structures of nearly all the individual components of chemoreceptor arrays, ECT has revealed the mesoscale information about how the components are arranged within cells. Receptors assemble into a universally conserved 12-nm hexagonal lattice linked by CheA/CheW rings. Membrane-bound arrays are single layered; cytoplasmic arrays are double layered. Images of in vitro reconstitutions have led to a model of how arrays assemble, and images of native arrays in different states have shown that the conformational changes associated with signal transduction are subtle, constraining models of activation and system cooperativity. Phase plates, better detectors, and more stable stages promise even higher resolution and broader application in the near future.
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Affiliation(s)
- Ariane Briegel
- Department of Biology, Leiden University, 2333 Leiden, Netherlands
| | - Grant Jensen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, California 91125; .,Howard Hughes Medical Institute, Pasadena, California 91125
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15
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Silverman SM, Moses JE, Sharpless KB. Reengineering Antibiotics to Combat Bacterial Resistance: Click Chemistry [1,2,3]-Triazole Vancomycin Dimers with Potent Activity against MRSA and VRE. Chemistry 2016; 23:79-83. [PMID: 27747932 DOI: 10.1002/chem.201604765] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Indexed: 01/22/2023]
Abstract
Vancomycin has long been considered a drug of last resort. Its efficiency in treating multiple drug-resistant bacterial infections, particularly methicillin-resistant Staphylococcus aureus (MRSA), has had a profound effect on the treatment of life-threatening infections. However, the emergence of resistance to vancomycin is a cause for significant worldwide concern, prompting the urgent development of new effective treatments for antibiotic resistant bacterial infections. Harnessing the benefits of multivalency and cooperativity against vancomycin-resistant strains, we report a Click Chemistry approach towards reengineered vancomycin derivatives and the synthesis of a number of dimers with increased potency against MRSA and vancomycin resistant Enterococci (VRE; VanB). These semi-synthetic dimeric ligands were linked together with great efficiency using the powerful CuAAC reaction, demonstrating high levels of selectivity and purity.
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Affiliation(s)
- Steven M Silverman
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - John E Moses
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.,School of Chemistry, University of Nottingham, Nottingham, NG7 2RD, UK
| | - K Barry Sharpless
- Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
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16
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Video processing analysis for the determination and evaluation of the chemotactic response in bacterial populations. J Microbiol Methods 2016; 127:146-153. [PMID: 27291715 DOI: 10.1016/j.mimet.2016.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/07/2016] [Accepted: 06/07/2016] [Indexed: 01/07/2023]
Abstract
The aim of the present work was to design a methodology based on video processing to obtain indicators of bacterial population motility that allow the quantitative and qualitative analysis and comparison of the chemotactic phenomenon with different attractants in the agarose-in plug bridge method. Video image sequences were processed applying Shannon's entropy to the intensity time series of each pixel, which conducted to a final pseudo colored image resembling a map of the dynamic bacterial clusters. Processed images could discriminate perfectly between positive and negative attractant responses at different periods of time from the beginning of the assay. An index of spatial and temporal motility was proposed to quantify the bacterial response. With this index, this video processing method allowed obtaining quantitative information of the dynamic changes in space and time from a traditional qualitative assay. We conclude that this computational technique, applied to the traditional agarose-in plug assay, has demonstrated good sensitivity for identifying chemotactic regions with a broad range of motility.
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Kimura Y, Saito N, Hanada K, Liu J, Okabe T, Kawashima SA, Yamatsugu K, Kanai M. Supramolecular Ligands for Histone Tails by Employing a Multivalent Display of Trisulfonated Calix[4]arenes. Chembiochem 2015; 16:2599-604. [DOI: 10.1002/cbic.201500448] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Yasuaki Kimura
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Japan Science and Technology Agency (JST); ERATO; Kanai Life Science Catalysis Project; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Nae Saito
- Drug Discovery Initiative; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kayo Hanada
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Jiaan Liu
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Takayoshi Okabe
- Drug Discovery Initiative; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Shigehiro A. Kawashima
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Japan Science and Technology Agency (JST); ERATO; Kanai Life Science Catalysis Project; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Kenzo Yamatsugu
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Japan Science and Technology Agency (JST); ERATO; Kanai Life Science Catalysis Project; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
| | - Motomu Kanai
- Graduate School of Pharmaceutical Sciences; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
- Japan Science and Technology Agency (JST); ERATO; Kanai Life Science Catalysis Project; 7-3-1 Hongo Bunkyo-ku Tokyo 113-0033 Japan
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18
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Affiliation(s)
- Yoshiko Miura
- Department of Chemical Engineering, Graduate
School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yu Hoshino
- Department of Chemical Engineering, Graduate
School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hirokazu Seto
- Department of Chemical Engineering, Graduate
School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
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19
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Greenswag AR, Li X, Borbat PP, Samanta D, Watts K, Freed JH, Crane BR. Preformed Soluble Chemoreceptor Trimers That Mimic Cellular Assembly States and Activate CheA Autophosphorylation. Biochemistry 2015; 54:3454-68. [PMID: 25967982 PMCID: PMC4772074 DOI: 10.1021/bi501570n] [Citation(s) in RCA: 14] [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: 12/31/2014] [Revised: 05/12/2015] [Indexed: 12/13/2022]
Abstract
Bacterial chemoreceptors associate with the histidine kinase CheA and coupling protein CheW to form extended membrane arrays that receive and transduce environmental signals. A receptor trimers-of-dimers resides at each vertex of the hexagonal protein lattice. CheA is fully activated and regulated when it is integrated into the receptor assembly. To mimic these states in solution, we have engineered chemoreceptor cytoplasmic kinase-control modules (KCMs) based on the Escherichia coli aspartate receptor Tar that are covalently fused and trimerized by a foldon domain (Tar(FO)). Small-angle X-ray scattering, multi-angle light scattering, and pulsed-dipolar electron spin resonance spectroscopy of spin-labeled proteins indicate that the Tar(FO) modules assemble into homogeneous trimers wherein the protein interaction regions closely associate at the end opposite to the foldon domains. The Tar(FO) variants greatly increase the saturation levels of phosphorylated CheA (CheA-P), indicating that the association with a trimer of receptor dimers changes the fraction of active kinase. However, the rate constants for CheA-P formation with the Tar variants are low compared to those for autophosphorylation by free CheA, and net phosphotransfer from CheA to CheY does not increase commensurately with CheA autophosphorylation. Thus, the Tar variants facilitate slow conversion to an active form of CheA that then undergoes stable autophosphorylation and is capable of subsequent phosphotransfer to CheY. Free CheA is largely incapable of phosphorylation but contains a small active fraction. Addition of Tar(FO) to CheA promotes a planar conformation of the regulatory domains consistent with array models for the assembly state of the ternary complex and different from that observed with a single inhibitory receptor. Introduction of Tar(FO) into E. coli cells activates endogenous CheA to produce increased clockwise flagellar rotation, with the effects increasing in the presence of the chemotaxis methylation system (CheB/CheR). Overall, the Tar(FO) modules demonstrate that trimerized signaling tips self-associate, bind CheA and CheW, and facilitate conversion of CheA to an active conformation.
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Affiliation(s)
- Anna R. Greenswag
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Xiaoxiao Li
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Peter P. Borbat
- Center
for Advanced ESR Studies, Cornell University, Ithaca, New York 14853, United States
| | - Dipanjan Samanta
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
| | - Kylie
J. Watts
- Division
of Microbiology and Molecular Genetics, Loma Linda University, Loma Linda, California 92350, United States
| | - Jack H. Freed
- Center
for Advanced ESR Studies, Cornell University, Ithaca, New York 14853, United States
| | - Brian R. Crane
- Department
of Chemistry and Chemical Biology, Cornell
University, Ithaca, New York 14853, United
States
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20
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Krabbenborg SO, Veerbeek J, Huskens J. Spatially Controlled Out-of-Equilibrium Host-Guest System under Electrochemical Control. Chemistry 2015; 21:9638-44. [DOI: 10.1002/chem.201501544] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Indexed: 12/29/2022]
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21
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Hiremath G, Hyakutake A, Yamamoto K, Ebisawa T, Nakamura T, Nishiyama SI, Homma M, Kawagishi I. Hypoxia-induced localization of chemotaxis-related signaling proteins inVibrio cholerae. Mol Microbiol 2015; 95:780-90. [DOI: 10.1111/mmi.12887] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/21/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Geetha Hiremath
- Research Center for Micro-Nano Technology; Hosei University; Koganei Tokyo 184-8584 Japan
| | - Akihiro Hyakutake
- Division of Biological Science; Graduate School of Science; Nagoya University; Chikusa-ku Nagoya 464-8602 Japan
| | - Kentaro Yamamoto
- Department of Frontier Bioscience; Hosei University; Koganei Tokyo 184-8584 Japan
| | - Tatsuaki Ebisawa
- Department of Frontier Bioscience; Hosei University; Koganei Tokyo 184-8584 Japan
| | - Tomoyuki Nakamura
- Department of Frontier Bioscience; Hosei University; Koganei Tokyo 184-8584 Japan
| | - So-ichiro Nishiyama
- Department of Frontier Bioscience; Hosei University; Koganei Tokyo 184-8584 Japan
| | - Michio Homma
- Division of Biological Science; Graduate School of Science; Nagoya University; Chikusa-ku Nagoya 464-8602 Japan
| | - Ikuro Kawagishi
- Research Center for Micro-Nano Technology; Hosei University; Koganei Tokyo 184-8584 Japan
- Department of Frontier Bioscience; Hosei University; Koganei Tokyo 184-8584 Japan
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22
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Bi S, Lai L. Bacterial chemoreceptors and chemoeffectors. Cell Mol Life Sci 2015; 72:691-708. [PMID: 25374297 PMCID: PMC11113376 DOI: 10.1007/s00018-014-1770-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 10/05/2014] [Accepted: 10/23/2014] [Indexed: 01/11/2023]
Abstract
Bacteria use chemotaxis signaling pathways to sense environmental changes. Escherichia coli chemotaxis system represents an ideal model that illustrates fundamental principles of biological signaling processes. Chemoreceptors are crucial signaling proteins that mediate taxis toward a wide range of chemoeffectors. Recently, in deep study of the biochemical and structural features of chemoreceptors, the organization of higher-order clusters in native cells, and the signal transduction mechanisms related to the on-off signal output provides us with general insights to understand how chemotaxis performs high sensitivity, precise adaptation, signal amplification, and wide dynamic range. Along with the increasing knowledge, bacterial chemoreceptors can be engineered to sense novel chemoeffectors, which has extensive applications in therapeutics and industry. Here we mainly review recent advances in the E. coli chemotaxis system involving structure and organization of chemoreceptors, discovery, design, and characterization of chemoeffectors, and signal recognition and transduction mechanisms. Possible strategies for changing the specificity of bacterial chemoreceptors to sense novel chemoeffectors are also discussed.
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Affiliation(s)
- Shuangyu Bi
- Center for Quantitative Biology, Peking University, Beijing, 100871 China
- Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany
| | - Luhua Lai
- Center for Quantitative Biology, Peking University, Beijing, 100871 China
- BNLMS, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, and Peking-Tsinghua Center for Life Sciences at College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871 China
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23
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Aoraha E, Candreva J, Kim JR. Engineering of a peptide probe for β-amyloid aggregates. MOLECULAR BIOSYSTEMS 2015; 11:2281-9. [DOI: 10.1039/c5mb00280j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A non-self-aggregating peptide ligand for β-amyloid aggregates created by simple point mutation of an β-amyloid-derived segment.
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Affiliation(s)
- Edwin Aoraha
- Othmer-Jacobs Department of Chemical and Biomolecular Engineering
- New York University
- Brooklyn
- USA
| | - Jason Candreva
- Othmer-Jacobs Department of Chemical and Biomolecular Engineering
- New York University
- Brooklyn
- USA
| | - Jin Ryoun Kim
- Othmer-Jacobs Department of Chemical and Biomolecular Engineering
- New York University
- Brooklyn
- USA
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24
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Gade M, Paul A, Alex C, Choudhury D, Thulasiram HV, Kikkeri R. Supramolecular scaffolds on glass slides as sugar based rewritable sensors for bacteria. Chem Commun (Camb) 2015; 51:6346-9. [DOI: 10.1039/c5cc01019e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We describe here the sugar functionalized β-cyclodextrin–ferrocene glass slides as fully reversible bacterial biosensors under the influence of external adamantane carboxylic acid.
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Affiliation(s)
- Madhuri Gade
- Indian Institute of Science Education and Research
- Pune 411008
- India
| | - Ajay Paul
- Chemical Biology Unit
- Division of Organic chemistry
- CSIR-National Chemical Laboratory
- Pune-411008
- India
| | - Catherine Alex
- Indian Institute of Science Education and Research
- Pune 411008
- India
| | - Devika Choudhury
- Department of Energy Science and Engineering
- IIT Bombay
- Mumbai-400076
- India
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25
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Najem S, Grant M. The chaser and the chased: a phase-field model of an immune response. SOFT MATTER 2014; 10:9715-9720. [PMID: 25365918 DOI: 10.1039/c4sm01842g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper we present a model for an immune response to an invading pathogen. Particularly, we follow the motion of a neutrophil as it migrates to the site of infection guided by chemical cues, a mechanism termed chemotaxis, with the ability to reorient itself as the pathogen changes its position. In the process, the cell undergoes morphological alterations, in addition to the structural changes observed at its leading edge. Also, we derive a condition for a successful immune reaction by relating the speed of the neutrophil to that of the pathogen and to the diffusion coefficient of the chemical attractant.
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Affiliation(s)
- Sara Najem
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ, USA.
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26
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Cecioni S, Imberty A, Vidal S. Glycomimetics versus Multivalent Glycoconjugates for the Design of High Affinity Lectin Ligands. Chem Rev 2014; 115:525-61. [DOI: 10.1021/cr500303t] [Citation(s) in RCA: 381] [Impact Index Per Article: 38.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Samy Cecioni
- CERMAV, Université Grenoble Alpes and CNRS, BP 53, F-38041 Grenoble Cedex 9, France
- Institut
de Chimie et Biochimie Moléculaires et Supramoléculaires,
Laboratoire de Chimie Organique 2 - Glycochimie, UMR 5246, Université Lyon 1 and CNRS, 43 Boulevard du 11 Novembre 1918, F-69622, Villeurbanne, France
| | - Anne Imberty
- CERMAV, Université Grenoble Alpes and CNRS, BP 53, F-38041 Grenoble Cedex 9, France
| | - Sébastien Vidal
- Institut
de Chimie et Biochimie Moléculaires et Supramoléculaires,
Laboratoire de Chimie Organique 2 - Glycochimie, UMR 5246, Université Lyon 1 and CNRS, 43 Boulevard du 11 Novembre 1918, F-69622, Villeurbanne, France
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27
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Abstract
The bacterial strategy of chemotaxis relies on temporal comparisons of chemical concentrations, where the probability of maintaining the current direction of swimming is modulated by changes in stimulation experienced during the recent past. A short-term memory required for such comparisons is provided by the adaptation system, which operates through the activity-dependent methylation of chemotaxis receptors. Previous theoretical studies have suggested that efficient navigation in gradients requires a well-defined adaptation rate, because the memory time scale needs to match the duration of straight runs made by bacteria. Here we demonstrate that the chemotaxis pathway of Escherichia coli does indeed exhibit a universal relation between the response magnitude and adaptation time which does not depend on the type of chemical ligand. Our results suggest that this alignment of adaptation rates for different ligands is achieved through cooperative interactions among chemoreceptors rather than through fine-tuning of methylation rates for individual receptors. This observation illustrates a yet-unrecognized function of receptor clustering in bacterial chemotaxis.
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28
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Pichlo M, Bungert-Plümke S, Weyand I, Seifert R, Bönigk W, Strünker T, Kashikar ND, Goodwin N, Müller A, Pelzer P, Van Q, Enderlein J, Klemm C, Krause E, Trötschel C, Poetsch A, Kremmer E, Kaupp UB, Körschen HG, Collienne U. High density and ligand affinity confer ultrasensitive signal detection by a guanylyl cyclase chemoreceptor. J Cell Biol 2014; 206:541-57. [PMID: 25135936 PMCID: PMC4137060 DOI: 10.1083/jcb.201402027] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 07/15/2014] [Indexed: 12/28/2022] Open
Abstract
Guanylyl cyclases (GCs), which synthesize the messenger cyclic guanosine 3',5'-monophosphate, control several sensory functions, such as phototransduction, chemosensation, and thermosensation, in many species from worms to mammals. The GC chemoreceptor in sea urchin sperm can decode chemoattractant concentrations with single-molecule sensitivity. The molecular and cellular underpinnings of such ultrasensitivity are not known for any eukaryotic chemoreceptor. In this paper, we show that an exquisitely high density of 3 × 10(5) GC chemoreceptors and subnanomolar ligand affinity provide a high ligand-capture efficacy and render sperm perfect absorbers. The GC activity is terminated within 150 ms by dephosphorylation steps of the receptor, which provides a means for precise control of the GC lifetime and which reduces "molecule noise." Compared with other ultrasensitive sensory systems, the 10-fold signal amplification by the GC receptor is surprisingly low. The hallmarks of this signaling mechanism provide a blueprint for chemical sensing in small compartments, such as olfactory cilia, insect antennae, or even synaptic boutons.
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Affiliation(s)
- Magdalena Pichlo
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543
| | - Stefanie Bungert-Plümke
- Marine Biological Laboratory, Woods Hole, MA 02543 Institute of Complex Systems (ICS-4), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Ingo Weyand
- Marine Biological Laboratory, Woods Hole, MA 02543 Institute of Complex Systems (ICS-4), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Reinhard Seifert
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543
| | - Wolfgang Bönigk
- Center of Advanced European Studies and Research, 53175 Bonn, Germany
| | - Timo Strünker
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543
| | - Nachiket Dilip Kashikar
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543 Sussex Neuroscience, School of Life Sciences, University of Sussex, Brighton BN1 9QG, England, UK
| | - Normann Goodwin
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543 Babraham Institute, Cambridge CB22 3AT, England, UK
| | - Astrid Müller
- Center of Advanced European Studies and Research, 53175 Bonn, Germany
| | - Patric Pelzer
- Marine Biological Laboratory, Woods Hole, MA 02543 Department of Functional Neuroanatomy, Institute of Anatomy and Cell Biology, Heidelberg University, 69120 Heidelberg, Germany
| | - Qui Van
- III. Physikalisches Institut, Universität Göttingen, 37077 Göttingen, Germany
| | - Jörg Enderlein
- III. Physikalisches Institut, Universität Göttingen, 37077 Göttingen, Germany
| | - Clementine Klemm
- Leibniz-Institut für Molekulare Pharmakologie, 13125 Berlin, Germany
| | - Eberhard Krause
- Leibniz-Institut für Molekulare Pharmakologie, 13125 Berlin, Germany
| | | | - Ansgar Poetsch
- Plant Biochemistry, Ruhr University Bochum. 44801 Bochum, Germany
| | - Elisabeth Kremmer
- Institut für Molekulare Immunologie, Helmholtz-Zentrum München, 81377 München, Germany
| | - U Benjamin Kaupp
- Center of Advanced European Studies and Research, 53175 Bonn, Germany Marine Biological Laboratory, Woods Hole, MA 02543
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29
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Magennis EP, Fernandez-Trillo F, Sui C, Spain SG, Bradshaw D, Churchley D, Mantovani G, Winzer K, Alexander C. Bacteria-instructed synthesis of polymers for self-selective microbial binding and labelling. NATURE MATERIALS 2014; 13:748-55. [PMID: 24813421 PMCID: PMC4286827 DOI: 10.1038/nmat3949] [Citation(s) in RCA: 98] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2013] [Accepted: 03/18/2014] [Indexed: 05/20/2023]
Abstract
The detection and inactivation of pathogenic strains of bacteria continues to be an important therapeutic goal. Hence, there is a need for materials that can bind selectively to specific microorganisms for diagnostic or anti-infective applications, but that can be formed from simple and inexpensive building blocks. Here, we exploit bacterial redox systems to induce a copper-mediated radical polymerization of synthetic monomers at cell surfaces, generating polymers in situ that bind strongly to the microorganisms that produced them. This 'bacteria-instructed synthesis' can be carried out with a variety of microbial strains, and we show that the polymers produced are self-selective binding agents for the 'instructing' cell types. We further expand on the bacterial redox chemistries to 'click' fluorescent reporters onto polymers directly at the surfaces of a range of clinical isolate strains, allowing rapid, facile and simultaneous binding and visualization of pathogens.
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Affiliation(s)
- E. Peter Magennis
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Francisco Fernandez-Trillo
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
- School of Chemistry, Haworth Building, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Cheng Sui
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
| | | | - David Bradshaw
- GlaxoSmithKline, St Georges Avenue, Weybridge, Surrey, UK
| | | | - Giuseppe Mantovani
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
- Correspondence and requests for materials should be addressed to C. A. : , Fax: +44 115 951 5102; Tel: +44 115 846 7678
| | - Klaus Winzer
- School of Molecular Medical Sciences, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Cameron Alexander
- School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK
- Correspondence and requests for materials should be addressed to C. A. : , Fax: +44 115 951 5102; Tel: +44 115 846 7678
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30
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Santos TMA, Lin TY, Rajendran M, Anderson SM, Weibel DB. Polar localization of Escherichia coli chemoreceptors requires an intact Tol-Pal complex. Mol Microbiol 2014; 92:985-1004. [PMID: 24720726 DOI: 10.1111/mmi.12609] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2014] [Indexed: 11/29/2022]
Abstract
Subcellular biomolecular localization is critical for the metabolic and structural properties of the cell. The functional implications of the spatiotemporal distribution of protein complexes during the bacterial cell cycle have long been acknowledged; however, the molecular mechanisms for generating and maintaining their dynamic localization in bacteria are not completely understood. Here we demonstrate that the trans-envelope Tol-Pal complex, a widely conserved component of the cell envelope of Gram-negative bacteria, is required to maintain the polar positioning of chemoreceptor clusters in Escherichia coli. Localization of the chemoreceptors was independent of phospholipid composition of the membrane and the curvature of the cell wall. Instead, our data indicate that chemoreceptors interact with components of the Tol-Pal complex and that this interaction is required to polarly localize chemoreceptor clusters. We found that disruption of the Tol-Pal complex perturbs the polar localization of chemoreceptors, alters cell motility, and affects chemotaxis. We propose that the E. coli Tol-Pal complex restricts mobility of the chemoreceptor clusters at the cell poles and may be involved in regulatory mechanisms that co-ordinate cell division and segregation of the chemosensory machinery.
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Affiliation(s)
- Thiago M A Santos
- Department of Biochemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA
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31
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Raissi AJ, Scangarello FA, Hulce KR, Pontrello JK, Paradis S. Enhanced potency of the metalloprotease inhibitor TAPI-2 by multivalent display. Bioorg Med Chem Lett 2014; 24:2002-7. [PMID: 24581919 PMCID: PMC4043442 DOI: 10.1016/j.bmcl.2014.02.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 01/27/2014] [Accepted: 02/04/2014] [Indexed: 11/25/2022]
Abstract
Metalloproteases regulate a vast array of critical cellular processes such as proliferation, migration, repair, and invasion/metastasis. In so doing, metalloproteases have been shown to play key roles in the pathogenesis of multiple disorders including arteriosclerosis, arthritis, cancer metastasis, and ischemic brain injury. Therefore, much work has focused on developing metalloprotease inhibitors to provide a potential therapeutic benefit against the progression of these and other diseases. In order to produce a more potent inhibitor of metalloproteases, we synthesized multivalent displays of a metalloprotease inhibitor derived from the ring-opening metathesis polymerization (ROMP). Specifically, multivalent ligands of a broad-spectrum metalloprotease inhibitor, TAPI-2, were generated upon conjugation of the amine-bearing inhibitor with the ROMP-derived N-hydroxysuccinimide ester polymer. By monitoring the metalloprotease dependent cleavage of the transmembrane protein Semaphorin4D (Sema4D), we demonstrated an enhancement of inhibition by multivalent TAPI-2 compared to monovalent TAPI-2. To further optimize the potency of the multivalent inhibitor, we systematically varied the polymer length and inhibitor ligand density (mole fraction, χ). We observed that while ligand density plays a modest role in the potency of inhibition caused by the multivalent TAPI-2 display, the length of the polymer produces a much greater effect on inhibitor potency, with the shortest polymer achieving the greatest level of inhibition. These findings validate the use of multivalent display to enhance the potency of metalloprotease inhibitors and further, suggest this may be a useful approach to enhance potency of other small molecule towards their targets.
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Affiliation(s)
- Aram J Raissi
- Department of Biology, National Center for Behavioral Genomics, and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02454, United States
| | - Frank A Scangarello
- Department of Biology, National Center for Behavioral Genomics, and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02454, United States; Department of Chemistry, Brandeis University, Waltham, MA 02454, United States
| | - Kaitlin R Hulce
- Department of Chemistry, Brandeis University, Waltham, MA 02454, United States
| | - Jason K Pontrello
- Department of Chemistry, Brandeis University, Waltham, MA 02454, United States.
| | - Suzanne Paradis
- Department of Biology, National Center for Behavioral Genomics, and Volen Center for Complex Systems, Brandeis University, Waltham, MA 02454, United States.
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Briegel A, Ladinsky MS, Oikonomou C, Jones CW, Harris MJ, Fowler DJ, Chang YW, Thompson LK, Armitage JP, Jensen GJ. Structure of bacterial cytoplasmic chemoreceptor arrays and implications for chemotactic signaling. eLife 2014; 3:e02151. [PMID: 24668172 PMCID: PMC3964821 DOI: 10.7554/elife.02151] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Most motile bacteria sense and respond to their environment through a transmembrane chemoreceptor array whose structure and function have been well-studied, but many species also contain an additional cluster of chemoreceptors in their cytoplasm. Although the cytoplasmic cluster is essential for normal chemotaxis in some organisms, its structure and function remain unknown. Here we use electron cryotomography to image the cytoplasmic chemoreceptor cluster in Rhodobacter sphaeroides and Vibrio cholerae. We show that just like transmembrane arrays, cytoplasmic clusters contain trimers-of-receptor-dimers organized in 12-nm hexagonal arrays. In contrast to transmembrane arrays, however, cytoplasmic clusters comprise two CheA/CheW baseplates sandwiching two opposed receptor arrays. We further show that cytoplasmic fragments of normally transmembrane E. coli chemoreceptors form similar sandwiched structures in the presence of molecular crowding agents. Together these results suggest that the 12-nm hexagonal architecture is fundamentally important and that sandwiching and crowding can replace the stabilizing effect of the membrane. DOI:http://dx.doi.org/10.7554/eLife.02151.001 Many bacteria swim through water by rotating tiny hair-like structures called flagella. In E. coli, if all the flagella on the surface of a bacterium rotate in a counterclockwise fashion, then it will swim in a particular direction, but if the flagella all rotate in an clockwise fashion, then the bacterium will stop swimming and start to tumble. Bacteria use a combination of swimming and tumbling in order to move towards or away from certain chemicals. For example, a bacterium is able to move towards a source of nutrients because it is constantly evaluating its environment and will swim forward for longer periods of time when it recognizes the concentration of the nutrient is increasing. And if it senses that the nutrient concentration is decreasing, it will tumble in an effort to move in a different direction. Many bacteria, such as E. coli, rely on proteins in their cell membrane called chemoreceptors to sense specific chemicals and then send signals that tell the flagella how to rotate. These transmembrane receptors and their role in chemotaxis—that is, movement towards or away from specific chemicals in the environment—have been widely studied. However, other bacteria also have chemoreceptors in the cytoplasm inside the bacterial cell, and much less is known about these. Now, Briegel et al. have examined the cytoplasmic chemoreceptors of two unrelated bacteria, R. sphaeroides and V. cholera, and found that the cytoplasmic chemoreceptors arrange themselves in hexagonal arrays, similar to the way that transmembrane chemoreceptors are arranged. However, the cytoplasmic chemoreceptors arrange themselves in a two-layer sandwich-like structure, whereas the transmembrane chemoreceptors are arranged in just one layer. The next step is to understand how chemical binding causes these arrays to send their signals to the motor. A complete understanding of this signaling system may ultimately allow scientists to re-engineer it to draw bacteria to targets of medical or environmental interest, such as cancer cells or contaminated soils. DOI:http://dx.doi.org/10.7554/eLife.02151.002
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Affiliation(s)
- Ariane Briegel
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
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Ortega DR, Mo G, Lee K, Zhou H, Baudry J, Dahlquist FW, Zhulin IB. Conformational coupling between receptor and kinase binding sites through a conserved salt bridge in a signaling complex scaffold protein. PLoS Comput Biol 2013; 9:e1003337. [PMID: 24244143 PMCID: PMC3828127 DOI: 10.1371/journal.pcbi.1003337] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 09/27/2013] [Indexed: 11/25/2022] Open
Abstract
Bacterial chemotaxis is one of the best studied signal transduction pathways. CheW is a scaffold protein that mediates the association of the chemoreceptors and the CheA kinase in a ternary signaling complex. The effects of replacing conserved Arg62 of CheW with other residues suggested that the scaffold protein plays a more complex role than simply binding its partner proteins. Although R62A CheW had essentially the same affinity for chemoreceptors and CheA, cells expressing the mutant protein are impaired in chemotaxis. Using a combination of molecular dynamics simulations (MD), NMR spectroscopy, and circular dichroism (CD), we addressed the role of Arg62. Here we show that Arg62 forms a salt bridge with another highly conserved residue, Glu38. Although this interaction is unimportant for overall protein stability, it is essential to maintain the correct alignment of the chemoreceptor and kinase binding sites of CheW. Computational and experimental data suggest that the role of the salt bridge in maintaining the alignment of the two partner binding sites is fundamental to the function of the signaling complex but not to its assembly. We conclude that a key feature of CheW is to maintain the specific geometry between the two interaction sites required for its function as a scaffold. Signal transduction is a universal biological process and a common target of drug design. The chemotaxis machinery in Escherichia coli is a model signal transduction system, and the CheW protein is one of its core components. CheW is thought to work as a scaffold protein that mediates the formation of the signaling complex with the CheA histidine kinase and the chemoreceptors. A mutation targeting a highly conserved residue, Arg62, impairs chemotaxis while maintaining normal binding affinity for both partners, suggesting that CheW might play a more complex role than previously proposed. Using a series of molecular dynamics simulations, we found that the residue Arg62 can form a stable salt bridge with another highly conserved residue, Glu38. We determined that this bridge does not contribute to the overall stability of the protein. However, the bridge stabilizes the local backbone structure of CheW and stabilizes the relative position of the binding sites for the chemoreceptor and kinase. The geometry of these interactions appears to be vital for the function of the signaling complex. We validated and complemented our computational findings using NMR spectroscopy and circular dichroism analysis.
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Affiliation(s)
- Davi R. Ortega
- Joint Institute for Computational Sciences, University of Tennessee - Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
- Department of Physics, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Guoya Mo
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, United States of America
| | - Kwangwoon Lee
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, United States of America
| | - Hongjun Zhou
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, United States of America
| | - Jerome Baudry
- Department of Biochemistry and Cell and Molecular Biology, University of Tennessee, Knoxville, Tennessee, United States of America
- Center for Molecular Biophysics, University of Tennessee - Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
| | - Frederick W. Dahlquist
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California, United States of America
| | - Igor B. Zhulin
- Joint Institute for Computational Sciences, University of Tennessee - Oak Ridge National Laboratory, Oak Ridge, Tennessee, United States of America
- Department of Microbiology, University of Tennessee, Knoxville, Tennessee, United States of America
- * E-mail:
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Chiu SW, Roberts MAJ, Leake MC, Armitage JP. Positioning of chemosensory proteins and FtsZ through the Rhodobacter sphaeroides cell cycle. Mol Microbiol 2013; 90:322-37. [PMID: 23944351 DOI: 10.1111/mmi.12366] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2013] [Indexed: 12/28/2022]
Abstract
Bacterial chemotaxis depends on signalling through large protein complexes. Each cell must inherit a complex on division, suggesting some co-ordination with cell division. In Escherichia coli the membrane-spanning chemosensory complexes are polar and new static complexes form at pre-cytokinetic sites, ensuring positioning at the new pole after division and suggesting a role for the bacterial cytoskeleton. Rhodobacter sphaeroides has both membrane-associated and cytoplasmic, chromosome-associated chemosensory complexes. We followed the relative positions of the two chemosensory complexes, FtsZ and MreB in aerobic and in photoheterotrophic R. sphaeroides cells using fluorescence microscopy. FtsZ forms polar spots after cytokinesis, which redistribute to the midcell forming nodes from which FtsZ extends circumferentially to form the Z-ring. Membrane-associated chemosensory proteins form a number of dynamic unit-clusters with mature clusters containing about 1000 CheW(3) proteins. Individual clusters diffuse randomly within the membrane, accumulating at new poles after division but not colocalizing with either FtsZ or MreB. The cytoplasmic complex colocalizes with FtsZ at midcells in new-born cells. Before cytokinesis one complex moves to a daughter cell, followed by the second moving to the other cell. These data indicate that two homologous complexes use different mechanisms to ensure partitioning, and neither complex utilizes FtsZ or MreB for positioning.
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Affiliation(s)
- Sheng-Wen Chiu
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK
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Jeong HH, Lee SH, Lee CS. Pump-less static microfluidic device for analysis of chemotaxis of Pseudomonas aeruginosa using wetting and capillary action. Biosens Bioelectron 2013; 47:278-84. [DOI: 10.1016/j.bios.2013.03.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Revised: 03/07/2013] [Accepted: 03/14/2013] [Indexed: 12/22/2022]
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Abstract
The spatial structure of the cell is highly organized at all levels: from small complexes and assemblies, to local nano- and microclusters, to global, micrometer scales across and between cells. We suggest that this multiscale spatial cell organization also organizes signaling and coordinates cellular behavior. We propose a new view of the spatial structure of cell signaling systems. This new view describes cell signaling in terms of dynamic allosteric interactions within and among distinct, spatially organized transient clusters. The clusters vary over time and space and are on length scales from nanometers to micrometers. When considered across these length scales, primary factors in the spatial organization are cell membrane domains and the actin cytoskeleton, both also highly dynamic. A key challenge is to understand the interplay across these multiple scales, link it to the physicochemical basis of the conformational behavior of single molecules and ultimately relate it to cellular function. Overall, our premise is that at these scales, cell signaling should be thought of not primarily as a sequence of diffusion-controlled molecular collisions, but instead transient, allostery-driven cluster re-forming interactions.
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Affiliation(s)
- Ruth Nussinov
- Basic Research Program, SAIC-Frederick, Inc., Cancer and Inflammation Program, National Cancer Institute, Frederick, MD 21702
- Sackler Inst. of Molecular Medicine, Department of Human Genetics and Molecular Medicine, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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Wang F, Cui X, Sun Y, Dong CH. Ethylene signaling and regulation in plant growth and stress responses. PLANT CELL REPORTS 2013; 32:1099-109. [PMID: 23525746 DOI: 10.1007/s00299-013-1421-6] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Revised: 02/28/2013] [Accepted: 03/09/2013] [Indexed: 05/19/2023]
Abstract
Gaseous phytohormone ethylene affects many aspects of plant growth and development. The ethylene signaling pathway starts when ethylene binds to its receptors. Since the cloning of the first ethylene receptor ETR1 from Arabidopsis, a large number of studies have steadily improved our understanding of the receptors and downstream components in ethylene signal transduction pathway. This article reviews the regulation of ethylene receptors, signal transduction, and the posttranscriptional modulation of downstream components. Functional roles and importance of the ethylene signaling components in plant growth and stress responses are also discussed. Cross-reactions of ethylene with auxin and other phytohormones in plant organ growth will be analyzed. The studies of ethylene signaling in plant growth, development, and stress responses in the past decade greatly advanced our knowledge of how plants respond to endogenous signals and environmental factors.
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Affiliation(s)
- Feifei Wang
- College of Life Sciences, Qingdao Agricultural University, 266109 Qingdao, People's Republic of China
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Gou Y, Geng J, Richards SJ, Burns J, Remzi Becer C, Haddleton DM. A Detailed Study on Understanding Glycopolymer Library and Con A Interactions. JOURNAL OF POLYMER SCIENCE. PART A, POLYMER CHEMISTRY 2013; 51:2588-2597. [PMID: 23761950 PMCID: PMC3677416 DOI: 10.1002/pola.26646] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 02/12/2013] [Indexed: 01/16/2023]
Abstract
Synthetic glycopolymers are important natural oligosaccharides mimics for many biological applications. To develop glycopolymeric drugs and therapeutic agents, factors that control the receptor-ligand interaction need to be investigated. A library of well-defined glycopolymers has been prepared by the combination of copper mediated living radical polymerization and CuAAC click reaction via post-functionalization of alkyne-containing precursor polymers with different sugar azides. Employing Concanavalin A as the model receptor, we explored the influence of the nature and densities of different sugars residues (mannose, galactose, and glucose) on the stoichiometry of the cluster, the rate of the cluster formation, the inhibitory potency of the glycopolymers, and the stability of the turbidity through quantitative precipitation assays, turbidimetry assays, inhibitory potency assays, and reversal aggregation assays. The diversities of binding properties contributed by different clustering parameters will make it possible to define the structures of the multivalent ligands and densities of binding epitopes tailor-made for specific functions in the lectin-ligand interaction. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2588-2597.
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Affiliation(s)
- Yanzi Gou
- Science and Technology on Advanced Ceramic Fibers and Composites Laboratory, National University of Defense Technology Changsha, 410073, China
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Abstract
Glycans are key participants in biological processes ranging from reproduction to cellular communication to infection. Revealing glycan roles and the underlying molecular mechanisms by which glycans manifest their function requires access to glycan derivatives that vary systematically. To this end, glycopolymers (polymers bearing pendant carbohydrates) have emerged as valuable glycan analogs. Because glycopolymers can readily be synthesized, their overall shape can be varied, and they can be altered systematically to dissect the structural features that underpin their activities. This review provides examples in which glycopolymers have been used to effect carbohydrate-mediated signal transduction. Our objective is to illustrate how these powerful tools can reveal the molecular mechanisms that underlie carbohydrate-mediated signal transduction.
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Affiliation(s)
- Laura L Kiessling
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI 53706, USA.
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Frank V, Vaknin A. Prolonged stimuli alter the bacterial chemosensory clusters. Mol Microbiol 2013; 88:634-44. [PMID: 23551504 DOI: 10.1111/mmi.12215] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/21/2013] [Indexed: 11/27/2022]
Abstract
The clustering of membrane-bound receptors plays an essential role in various biological systems. A notable model system for studying this phenomenon is the bacterial chemosensory cluster that allows motile bacteria to navigate along chemical gradients in their environment. While the basic structure of these chemosensory clusters is becoming clear, their dynamic nature and operation are not yet understood. By measuring the fluorescence polarization of tagged receptor clusters in live Escherichia coli cells, we provide evidence for stimulus-induced dynamics in these sensory clusters. We find that when a stimulus is applied, the packing of the receptors slowly decreases and that the process reverses when the stimulus is removed. Consistent with these physical changes we find that the effective cooperativity of the kinase response slowly evolves in the presence of a stimulus. Time-lapse fluorescence imaging indicates that, despite these changes, the receptor clusters do not generally dissociate upon ligand binding. These data reveal stimulus-dependent plasticity in chemoreceptor clusters.
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Affiliation(s)
- Vered Frank
- The Racah Institute of Physics, The Hebrew University, Jerusalem, 91904, Israel
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Munoz EM, Correa J, Riguera R, Fernandez-Megia E. Real-Time Evaluation of Binding Mechanisms in Multivalent Interactions: A Surface Plasmon Resonance Kinetic Approach. J Am Chem Soc 2013; 135:5966-9. [DOI: 10.1021/ja400951g] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Eva Maria Munoz
- Department of Organic
Chemistry and Center for Research
in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Jenaro de la
Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Juan Correa
- Department of Organic
Chemistry and Center for Research
in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Jenaro de la
Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Ricardo Riguera
- Department of Organic
Chemistry and Center for Research
in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Jenaro de la
Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Eduardo Fernandez-Megia
- Department of Organic
Chemistry and Center for Research
in Biological Chemistry and Molecular Materials (CIQUS), University of Santiago de Compostela, Jenaro de la
Fuente s/n, 15782 Santiago de Compostela, Spain
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42
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Euglena-based neurocomputing with two-dimensional optical feedback on swimming cells in micro-aquariums. Appl Soft Comput 2013. [DOI: 10.1016/j.asoc.2012.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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43
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Kim T, Lee H, Kim Y, Nam JM, Lee M. Protein-coated nanofibers for promotion of T cell activity. Chem Commun (Camb) 2013; 49:3949-51. [DOI: 10.1039/c3cc41215f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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44
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Miki K, Inoue T, Ohe K. Metathesis Polymerization-Based Synthesis of Functionalized Polymers Aiming at Medicinal Application. J SYN ORG CHEM JPN 2013. [DOI: 10.5059/yukigoseikyokaishi.71.601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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45
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Hsu SH, Yilmaz MD, Reinhoudt DN, Velders AH, Huskens J. Nonlinear Amplification of a Supramolecular Complex at a Multivalent Interface. Angew Chem Int Ed Engl 2012; 52:714-9. [DOI: 10.1002/anie.201207647] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Indexed: 11/12/2022]
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46
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Nonlinear Amplification of a Supramolecular Complex at a Multivalent Interface. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201207647] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Gour N, Barman AK, Verma S. Controlling morphology of peptide-based soft structures by covalent modifications. J Pept Sci 2012; 18:405-12. [DOI: 10.1002/psc.2411] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 03/03/2012] [Accepted: 03/08/2012] [Indexed: 11/08/2022]
Affiliation(s)
- Nidhi Gour
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur-208 016 UP India
- Department of Inorganic, Analytical and Applied Chemistry; University of Geneva-Sciences II; 30, quai Ernest-Ansermet CH-1211 Geneva 4 Switzerland
| | - Apurba K. Barman
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur-208 016 UP India
| | - Sandeep Verma
- Department of Chemistry; Indian Institute of Technology Kanpur; Kanpur-208 016 UP India
- DST Unit of Excellence in Soft Nanofabrication; Indian Institute of Technology Kanpur; Kanpur-208 016 UP India
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48
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Miura Y. Design and synthesis of well-defined glycopolymers for the control of biological functionalities. Polym J 2012. [DOI: 10.1038/pj.2012.4] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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49
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Si G, Yang W, Bi S, Luo C, Ouyang Q. A parallel diffusion-based microfluidic device for bacterial chemotaxis analysis. LAB ON A CHIP 2012; 12:1389-94. [PMID: 22361931 DOI: 10.1039/c2lc21219f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We developed a multiple-channel microfluidic device for bacterial chemotaxis detection. Some characteristics such as easy operation, parallel sample adding design and fast result readout make this device convenient for most biology labs. The characteristic feature of the design is the agarose gel channels, which serve as a semi-permeable membrane. They can stop the fluid flow and prevent bacteria getting across, but permit the diffusion of small molecules. In the device fabrication process a novel thermal-based method was used to control the shape of agarose gel in the microfluidic channel. The chemical gradient is established by diffusion which can be precisely controlled and measured. Combined with an 8-channel pipette, different attractants, repellent chemicals or different bacteria were analyzed by a two step operation with a readout time of one hour. This device may be useful in the high throughput detection of chemotaxis related molecules and genes.
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Affiliation(s)
- Guangwei Si
- The State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
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50
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Cloninger MJ, Bilgiçer B, Li L, Mangold SL, Phillips ST, Wolfenden ML. Multivalency. Supramol Chem 2012. [DOI: 10.1002/9780470661345.smc008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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