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Michael J. Danson - One of the best experts on this subject based on the ideXlab platform.
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the catalytic core of an archaeal 2 oxoacid dehydrogenase Multienzyme complex is a 42 mer protein assembly
FEBS Journal, 2012Co-Authors: Nia L. Marrott, Michael J. Danson, Jacqueline J. T. Marshall, Dmitri I. Svergun, Susan J. Crennell, Jean M. H. Van Den ElsenAbstract:The dihydrolipoyl acyl-transferase (E2) enzyme forms the structural and catalytic core of the tripartite 2-oxoacid dehydrogenase Multienzyme Complexes of the central metabolic pathways. Although this family of Multienzyme Complexes shares a common architecture, their E2 cores form homo-trimers that, depending on the source, further associate into either octahedral (24-mer) or icosahedral (60-mer) assemblies, as predicted by the principles of quasi-equivalence. In the crystal structure of the E2 core from Thermoplasma acidophilum, a thermophilic archaeon, the homo-trimers assemble into a unique 42-mer oblate spheroid. Analytical equilibrium centrifugation and small-angle X-ray scattering analyses confirm that this catalytically active 1.08 MDa assembly exists as a single species in solution, forming a hollow spheroid with a maximum diameter of 220 A. In this paper we show that a monodisperse macromolecular assembly, built from identical subunits in non-identical environments, forms an irregular protein shell via non-equivalent interactions. This unusually irregular protein shell, combining cubic and dodecahedral geometrical elements, expands on the concept of quasi-equivalence as a basis for understanding macromolecular assemblies by showing that cubic point group symmetry is not a physical requirement in Multienzyme assembly. These results extend our basic knowledge of protein assembly and greatly expand the number of possibilities to manipulate self-assembling biological Complexes to be utilized in innovative nanotechnology applications. Database The final coordinates of the E2 structure have been deposited in the Protein Data Bank (PDB accession code 3RQC) Structured digital abstract • E2 and E2 bind by x-ray crystallography (View interaction) • E2 and E2 bind by x ray scattering (View interaction)
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The catalytic core of an archaeal 2‐oxoacid dehydrogenase Multienzyme complex is a 42‐mer protein assembly
FEBS Journal, 2012Co-Authors: Nia L. Marrott, Michael J. Danson, Jacqueline J. T. Marshall, Dmitri I. Svergun, Susan J. Crennell, Jean M. H. Van Den ElsenAbstract:The dihydrolipoyl acyl-transferase (E2) enzyme forms the structural and catalytic core of the tripartite 2-oxoacid dehydrogenase Multienzyme Complexes of the central metabolic pathways. Although this family of Multienzyme Complexes shares a common architecture, their E2 cores form homo-trimers that, depending on the source, further associate into either octahedral (24-mer) or icosahedral (60-mer) assemblies, as predicted by the principles of quasi-equivalence. In the crystal structure of the E2 core from Thermoplasma acidophilum, a thermophilic archaeon, the homo-trimers assemble into a unique 42-mer oblate spheroid. Analytical equilibrium centrifugation and small-angle X-ray scattering analyses confirm that this catalytically active 1.08 MDa assembly exists as a single species in solution, forming a hollow spheroid with a maximum diameter of 220 A. In this paper we show that a monodisperse macromolecular assembly, built from identical subunits in non-identical environments, forms an irregular protein shell via non-equivalent interactions. This unusually irregular protein shell, combining cubic and dodecahedral geometrical elements, expands on the concept of quasi-equivalence as a basis for understanding macromolecular assemblies by showing that cubic point group symmetry is not a physical requirement in Multienzyme assembly. These results extend our basic knowledge of protein assembly and greatly expand the number of possibilities to manipulate self-assembling biological Complexes to be utilized in innovative nanotechnology applications. Database The final coordinates of the E2 structure have been deposited in the Protein Data Bank (PDB accession code 3RQC) Structured digital abstract • E2 and E2 bind by x-ray crystallography (View interaction) • E2 and E2 bind by x ray scattering (View interaction)
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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Discovery of the catalytic function of a putative 2-oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon Thermoplasma acidophilum.
FEBS letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an alpha2beta2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
Caroline Heath - One of the best experts on this subject based on the ideXlab platform.
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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Discovery of the catalytic function of a putative 2-oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon Thermoplasma acidophilum.
FEBS letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an alpha2beta2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
Alex C Jeffries - One of the best experts on this subject based on the ideXlab platform.
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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discovery of the catalytic function of a putative 2 oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon thermoplasma acidophilum
FEBS Letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an α2β2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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Discovery of the catalytic function of a putative 2-oxoacid dehydrogenase Multienzyme complex in the thermophilic archaeon Thermoplasma acidophilum.
FEBS letters, 2004Co-Authors: Caroline Heath, Alex C Jeffries, Michael J. DansonAbstract:Those aerobic archaea whose genomes have been sequenced possess a single 4-gene operon that, by sequence comparisons with Bacteria and Eukarya, appears to encode the three component enzymes of a 2-oxoacid dehydrogenase Multienzyme complex. However, no catalytic activity of any such complex has ever been detected in the Archaea. In the current paper, we have cloned and expressed the first two genes of this operon from the thermophilic archaeon, Thermoplasma acidophilum. We demonstrate that the protein products form an alpha2beta2 hetero-tetramer possessing the decarboxylase catalytic activity characteristic of the first component enzyme of a branched-chain 2-oxoacid dehydrogenase Multienzyme complex. This represents the first report of the catalytic function of these putative archaeal Multienzyme Complexes.
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Multienzyme Complexes in the Archaea: Predictions from Genome Sequences
Halophilic Microorganisms, 2004Co-Authors: Michael J. Danson, Alex C Jeffries, David J. Morgan, Michael L. Dyall-smithAbstract:Aerobic Bacteria and Eukarya possess a family of 2-oxoacid dehydrogenase Multienzyme Complexes that catalyse the general reaction:
Jiang Xia - One of the best experts on this subject based on the ideXlab platform.
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Synthetic Multienzyme Complexes Assembled on Virus-like Particles for Cascade Biosynthesis In Cellulo.
Bioconjugate chemistry, 2020Co-Authors: Qixin Wei, Jiang XiaAbstract:Multienzyme Complexes, or metabolons, are natural assemblies or clusters of sequential enzymes in biosynthesis. Spatial proximity of the enzyme active sites results in a substrate channeling effect...
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synthetic Multienzyme Complexes assembled on virus like particles for cascade biosynthesis in cellulo
Bioconjugate Chemistry, 2020Co-Authors: Qixin Wei, Jiang XiaAbstract:Multienzyme Complexes, or metabolons, are natural assemblies or clusters of sequential enzymes in biosynthesis. Spatial proximity of the enzyme active sites results in a substrate channeling effect, streamlines the cascade reaction, and increases the overall efficiency of the metabolic pathway. Engineers have constructed synthetic Multienzyme Complexes to acquire better control of the metabolic flux and a higher titer of the target product. As most of these Complexes are assembled through orthogonal interactions or bioconjugation reactions, the number of enzymes to be assembled is limited by the number of orthogonal interaction or reaction pairs. Here, we utilized the Tobacco mosaic virus (TMV) virus-like particle (VLP) as protein scaffold and orthogonal reactive protein pairs (SpyCatcher/SpyTag and SnoopCatcher/SnoopTag) as linker modules to assemble three terpene biosynthetic enzymes in Escherichia coli. The enzyme assembly switched on the production of amorpha-4,11-diene, whereas the product was undetectable in all the controls without assembly. This work demonstrates a facile strategy for constructing scaffolded catalytic nanomachineries to biosynthesize valuable metabolites in bacterial cells, and a unique assembly induced the switch-on mechanism in biosynthesis for the first time.
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Cascade Biocatalysis by Multienzyme–Nanoparticle Assemblies
2014Co-Authors: Wei Kang, Jiahui Liu, Jianpeng Wang, Yunyu Nie, Zhihong Guo, Jiang XiaAbstract:Multienzyme Complexes are of paramount importance in biosynthesis in cells. Yet, how sequential enzymes of cascade catalytic reactions synergize their activities through spatial organization remains elusive. Recent development of site-specific protein–nanoparticle conjugation techniques enables us to construct Multienzyme assemblies using nanoparticles as the template. Sequential enzymes in menaquinone biosynthetic pathway were conjugated to CdSe-ZnS quantum dots (QDs, a nanosized particulate material) through metal-affinity driven self-assembly. The assemblies were characterized by electrophoretic methods, the catalytic activities were monitored by reverse-phase chromatography, and the composition of the Multienzyme–QD assemblies was optimized through a progressive approach to achieve highly efficient catalytic conversion. Shorter enzyme–enzyme distance was discovered to facilitate intermediate transfer, and a fine control on the stoichiometric ratio of the assembly was found to be critical for the maximal synergy between the enzymes. Multienzyme–QD assemblies thereby provide an effective model to scrutinize the synergy of cascade enzymes in Multienzyme Complexes
Edward A. Bayer - One of the best experts on this subject based on the ideXlab platform.
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cellulosomes bacterial nanomachines for dismantling plant polysaccharides
Nature Reviews Microbiology, 2017Co-Authors: Lior Artzi, Edward A. Bayer, Sarah MoraïsAbstract:Cellulosomes are sophisticated multicomponent Complexes that are used by bacteria to degrade cellulose from plant cell walls. In this review, Artzi, Bayer and Morais explore the structural and functional diversity of cellulosomes and their applications; for example, in microbial biofuel production. Cellulosomes are Multienzyme Complexes that are produced by anaerobic cellulolytic bacteria for the degradation of lignocellulosic biomass. They comprise a complex of scaffoldin, which is the structural subunit, and various enzymatic subunits. The intersubunit interactions in these Multienzyme Complexes are mediated by cohesin and dockerin modules. Cellulosome-producing bacteria have been isolated from a large variety of environments, which reflects their prevalence and the importance of this microbial enzymatic strategy. In a given species, cellulosomes exhibit intrinsic heterogeneity, and between species there is a broad diversity in the composition and configuration of cellulosomes. With the development of modern technologies, such as genomics and proteomics, the full protein content of cellulosomes and their expression levels can now be assessed and the regulatory mechanisms identified. Owing to their highly efficient organization and hydrolytic activity, cellulosomes hold immense potential for application in the degradation of biomass and are the focus of much effort to engineer an ideal microorganism for the conversion of lignocellulose to valuable products, such as biofuels.
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Cellulosomes: bacterial nanomachines for dismantling plant polysaccharides
Nature Reviews Microbiology, 2017Co-Authors: Lior Artzi, Edward A. Bayer, Sarah MoraïsAbstract:Cellulosomes are sophisticated multicomponent Complexes that are used by bacteria to degrade cellulose from plant cell walls. In this review, Artzi, Bayer and Moraïs explore the structural and functional diversity of cellulosomes and their applications; for example, in microbial biofuel production. Cellulosomes are Multienzyme Complexes that are produced by anaerobic cellulolytic bacteria for the degradation of lignocellulosic biomass. They comprise a complex of scaffoldin, which is the structural subunit, and various enzymatic subunits. The intersubunit interactions in these Multienzyme Complexes are mediated by cohesin and dockerin modules. Cellulosome-producing bacteria have been isolated from a large variety of environments, which reflects their prevalence and the importance of this microbial enzymatic strategy. In a given species, cellulosomes exhibit intrinsic heterogeneity, and between species there is a broad diversity in the composition and configuration of cellulosomes. With the development of modern technologies, such as genomics and proteomics, the full protein content of cellulosomes and their expression levels can now be assessed and the regulatory mechanisms identified. Owing to their highly efficient organization and hydrolytic activity, cellulosomes hold immense potential for application in the degradation of biomass and are the focus of much effort to engineer an ideal microorganism for the conversion of lignocellulose to valuable products, such as biofuels. Cellulosomes are self-assembled Multienzyme Complexes that are highly efficient at degrading lignocellulose, mainly owing to common substrate targeting and consequent enzyme proximity that, together, generate substrate channelling and synergistic action. Cellulosomes have been identified in several anaerobic bacteria, with each species presenting its own molecular arrangement with varying degrees of complexity. The prevalence of cellulosomes as rare but central components in various ecosystems reflects the benefits of this enzymatic strategy. The cohesin–dockerin interaction has been studied extensively and is one of the strongest non-covalent interactions known in nature. The composition of cellulosomes is regulated and varied by the nature of the growth substrate (carbon source) of the parent bacterium. The cellulosome, as one of the most efficient machineries for the degradation of plant cell walls, can potentially be used for the large-scale conversion of biomass. Owing to the modular nature of cellulosomes, cellulosomal components have been proposed for use in additional biotechnological applications, notably, together with other affinity systems.
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single binding mode integration of hemicellulose degrading enzymes via adaptor scaffoldins in ruminococcus flavefaciens cellulosome
Journal of Biological Chemistry, 2016Co-Authors: Pedro Bule, Victor D. Alves, Luís M. A. Ferreira, Andre Leitao, Steven P Smith, Shabir Najmudin, Edward A. Bayer, Harry J Gilbert, Carlos M. G. A. FontesAbstract:: The assembly of one of Nature's most elaborate Multienzyme Complexes, the cellulosome, results from the binding of enzyme-borne dockerins to reiterated cohesin domains located in a non-catalytic primary scaffoldin. Generally, dockerins present two similar cohesin-binding interfaces that support a dual binding mode. The dynamic integration of enzymes in cellulosomes, afforded by the dual binding mode, is believed to incorporate additional flexibility in highly populated Multienzyme Complexes. Ruminococcus flavefaciens, the primary degrader of plant structural carbohydrates in the rumen of mammals, uses a portfolio of more than 220 different dockerins to assemble the most intricate cellulosome known to date. A sequence-based analysis organized R. flavefaciens dockerins into six groups. Strikingly, a subset of R. flavefaciens cellulosomal enzymes, comprising dockerins of groups 3 and 6, were shown to be indirectly incorporated into primary scaffoldins via an adaptor scaffoldin termed ScaC. Here, we report the crystal structure of a group 3 R. flavefaciens dockerin, Doc3, in complex with ScaC cohesin. Doc3 is unusual as it presents a large cohesin-interacting surface that lacks the structural symmetry required to support a dual binding mode. In addition, dockerins of groups 3 and 6, which bind exclusively to ScaC cohesin, display a conserved mechanism of protein recognition that is similar to Doc3. Groups 3 and 6 dockerins are predominantly appended to hemicellulose-degrading enzymes. Thus, single binding mode dockerins interacting with adaptor scaffoldins exemplify an evolutionary pathway developed by R. flavefaciens to recruit hemicellulases to the sophisticated cellulosomes acting in the gastrointestinal tract of mammals.
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Cell-surface Attachment of Bacterial Multienzyme Complexes Involves Highly Dynamic Protein-Protein Anchors
The Journal of biological chemistry, 2015Co-Authors: Kate Cameron, Pedro Bule, Victor D. Alves, Luís M. A. Ferreira, Steven P Smith, Shabir Najmudin, Edward A. Bayer, Harry J Gilbert, Helen Waller, Carlos M. G. A. FontesAbstract:Abstract Protein-protein interactions play a pivotal role in the assembly of the cellulosome, one of nature's most intricate nanomachines dedicated to the depolymerization of complex carbohydrates. The integration of cellulosomal components usually occurs through the binding of type I dockerin modules located at the C terminus of the enzymes to cohesin modules located in the primary scaffoldin subunit. Cellulosomes are typically recruited to the cell surface via type II cohesin-dockerin interactions established between primary and cell-surface anchoring scaffoldin subunits. In contrast with type II interactions, type I dockerins usually display a dual binding mode that may allow increased conformational flexibility during cellulosome assembly. Acetivibrio cellulolyticus produces a highly complex cellulosome comprising an unusual adaptor scaffoldin, ScaB, which mediates the interaction between the primary scaffoldin, ScaA, through type II cohesin-dockerin interactions and the anchoring scaffoldin, ScaC, via type I cohesin-dockerin interactions. Here, we report the crystal structure of the type I ScaB dockerin in complex with a type I ScaC cohesin in two distinct orientations. The data show that the ScaB dockerin displays structural symmetry, reflected by the presence of two essentially identical binding surfaces. The complex interface is more extensive than those observed in other type I Complexes, which results in an ultra-high affinity interaction (Ka ∼1012 m). A subset of ScaB dockerin residues was also identified as modulating the specificity of type I cohesin-dockerin interactions in A. cellulolyticus. This report reveals that recruitment of cellulosomes onto the cell surface may involve dockerins presenting a dual binding mode to incorporate additional flexibility into the quaternary structure of highly populated Multienzyme Complexes.
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The cellulosome — A treasure-trove for biotechnology
Trends in Biotechnology, 1994Co-Authors: Edward A. Bayer, Ely Morag, Raphael LamedAbstract:Abstract The cellulases of many cellulolytic bacteria are organized into discrete Multienzyme Complexes, called cellulosomes. The multiple subunits of cellulosomes are composed of numerous functional domains, which interact with each other and with the cellulosic substrate. One of these subunits comprises a distinctive new class of noncatalytic scaffolding polypeptide, which selectively integrates the various cellulase and xylanase subunits into the cohesive complex. Intelligent application of cellulosome hybrids and chimeric constructs of cellulosomal domains should enable better use of cellulosic biomass and may offer a wide range of novel applications in research, medicine and industry.