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  1. Article ; Online: A strategy for large-scale comparison of evolutionary- and reaction-based classifications of enzyme function.

    Holliday, Gemma L / Brown, Shoshana D / Mischel, David / Polacco, Benjamin J / Babbitt, Patricia C

    Database : the journal of biological databases and curation

    2020  Volume 2020

    Abstract: Determining the molecular function of enzymes discovered by genome sequencing represents a primary foundation for understanding many aspects of biology. Historically, classification of enzyme reactions has used the enzyme nomenclature system developed to ...

    Abstract Determining the molecular function of enzymes discovered by genome sequencing represents a primary foundation for understanding many aspects of biology. Historically, classification of enzyme reactions has used the enzyme nomenclature system developed to describe the overall reactions performed by biochemically characterized enzymes, irrespective of their associated sequences. In contrast, functional classification and assignment for the millions of protein sequences of unknown function now available is largely done in two computational steps, first by similarity-based assignment of newly obtained sequences to homologous groups, followed by transferring to them the known functions of similar biochemically characterized homologs. Due to the fundamental differences in their etiologies and practice, `how' these chemistry- and evolution-centric functional classification systems relate to each other has been difficult to explore on a large scale. To investigate this issue in a new way, we integrated two published ontologies that had previously described each of these classification systems independently. The resulting infrastructure was then used to compare the functional assignments obtained from each classification system for the well-studied and functionally diverse enolase superfamily. Mapping these function assignments to protein structure and reaction similarity networks shows a profound and complex disconnect between the homology- and chemistry-based classification systems. This conclusion mirrors previous observations suggesting that except for closely related sequences, facile annotation transfer from small numbers of characterized enzymes to the huge number uncharacterized homologs to which they are related is problematic. Our extension of these comparisons to large enzyme superfamilies in a computationally intelligent manner provides a foundation for new directions in protein function prediction for the huge proportion of sequences of unknown function represented in major databases. Interactive sequence, reaction, substrate and product similarity networks computed for this work for the enolase and two other superfamilies are freely available for download from the Structure Function Linkage Database Archive (http://sfld.rbvi.ucsf.edu).
    MeSH term(s) Computational Biology/methods ; Databases, Protein ; Enzymes/chemistry ; Enzymes/classification ; Enzymes/physiology ; Molecular Sequence Annotation ; Structure-Activity Relationship
    Chemical Substances Enzymes
    Language English
    Publishing date 2020-05-25
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2496706-3
    ISSN 1758-0463 ; 1758-0463
    ISSN (online) 1758-0463
    ISSN 1758-0463
    DOI 10.1093/database/baaa034
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: A global analysis of function and conservation of catalytic residues in enzymes.

    Ribeiro, António J M / Tyzack, Jonathan D / Borkakoti, Neera / Holliday, Gemma L / Thornton, Janet M

    The Journal of biological chemistry

    2019  Volume 295, Issue 2, Page(s) 314–324

    Abstract: The catalytic residues of an enzyme comprise the amino acids located in the active center responsible for accelerating the enzyme-catalyzed reaction. These residues lower the activation energy of reactions by performing several catalytic functions. ... ...

    Abstract The catalytic residues of an enzyme comprise the amino acids located in the active center responsible for accelerating the enzyme-catalyzed reaction. These residues lower the activation energy of reactions by performing several catalytic functions. Decades of enzymology research has established general themes regarding the roles of specific residues in these catalytic reactions, but it has been more difficult to explore these roles in a more systematic way. Here, we review the data on the catalytic residues of 648 enzymes, as annotated in the Mechanism and Catalytic Site Atlas (M-CSA), and compare our results with those in previous studies. We structured this analysis around three key properties of the catalytic residues: amino acid type, catalytic function, and sequence conservation in homologous proteins. As expected, we observed that catalysis is mostly accomplished by a small set of residues performing a limited number of catalytic functions. Catalytic residues are typically highly conserved, but to a smaller degree in homologues that perform different reactions or are nonenzymes (pseudoenzymes). Cross-analysis yielded further insights revealing which residues perform particular functions and how often. We obtained more detailed specificity rules for certain functions by identifying the chemical group upon which the residue acts. Finally, we show the mutation tolerance of the catalytic residues based on their roles. The characterization of the catalytic residues, their functions, and conservation, as presented here, is key to understanding the impact of mutations in evolution, disease, and enzyme design. The tools developed for this analysis are available at the M-CSA website and allow for user specific analysis of the same data.
    MeSH term(s) Amino Acid Sequence ; Amino Acids/chemistry ; Amino Acids/metabolism ; Animals ; Biocatalysis ; Catalytic Domain ; Conserved Sequence ; Databases, Protein ; Enzymes/chemistry ; Enzymes/metabolism ; Humans
    Chemical Substances Amino Acids ; Enzymes
    Language English
    Publishing date 2019-12-03
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 2997-x
    ISSN 1083-351X ; 0021-9258
    ISSN (online) 1083-351X
    ISSN 0021-9258
    DOI 10.1074/jbc.REV119.006289
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Evaluating Functional Annotations of Enzymes Using the Gene Ontology.

    Holliday, Gemma L / Davidson, Rebecca / Akiva, Eyal / Babbitt, Patricia C

    Methods in molecular biology (Clifton, N.J.)

    2016  Volume 1446, Page(s) 111–132

    Abstract: The Gene Ontology (GO) (Ashburner et al., Nat Genet 25(1):25-29, 2000) is a powerful tool in the informatics arsenal of methods for evaluating annotations in a protein dataset. From identifying the nearest well annotated homologue of a protein of ... ...

    Abstract The Gene Ontology (GO) (Ashburner et al., Nat Genet 25(1):25-29, 2000) is a powerful tool in the informatics arsenal of methods for evaluating annotations in a protein dataset. From identifying the nearest well annotated homologue of a protein of interest to predicting where misannotation has occurred to knowing how confident you can be in the annotations assigned to those proteins is critical. In this chapter we explore what makes an enzyme unique and how we can use GO to infer aspects of protein function based on sequence similarity. These can range from identification of misannotation or other errors in a predicted function to accurate function prediction for an enzyme of entirely unknown function. Although GO annotation applies to any gene products, we focus here a describing our approach for hierarchical classification of enzymes in the Structure-Function Linkage Database (SFLD) (Akiva et al., Nucleic Acids Res 42(Database issue):D521-530, 2014) as a guide for informed utilisation of annotation transfer based on GO terms.
    MeSH term(s) Animals ; Computational Biology/methods ; Databases, Protein ; Enzymes/classification ; Enzymes/genetics ; Enzymes/metabolism ; Gene Ontology ; Humans ; Molecular Sequence Annotation/methods
    Chemical Substances Enzymes
    Language English
    Publishing date 2016-11-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-4939-3743-1_9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Exploring the biological and chemical complexity of the ligases.

    Holliday, Gemma L / Rahman, Syed Asad / Furnham, Nicholas / Thornton, Janet M

    Journal of molecular biology

    2014  Volume 426, Issue 10, Page(s) 2098–2111

    Abstract: Using a novel method to map and cluster chemical reactions, we have re-examined the chemistry of the ligases [Enzyme Commission (EC) Class 6] and their associated protein families in detail. The type of bond formed by the ligase can be automatically ... ...

    Abstract Using a novel method to map and cluster chemical reactions, we have re-examined the chemistry of the ligases [Enzyme Commission (EC) Class 6] and their associated protein families in detail. The type of bond formed by the ligase can be automatically extracted from the equation of the reaction, replicating the EC subclass division. However, this subclass division hides considerable complexities, especially for the C-N forming ligases, which fall into at least three distinct types. The lower levels of the EC classification for ligases are somewhat arbitrary in their definition and add little to understanding their chemistry or evolution. By comparing the multi-domain architecture of the enzymes and using sequence similarity networks, we examined the links between overall reaction and evolution of the ligases. These show that, whilst many enzymes that perform the same overall chemistry group together, both convergent (similar function, different ancestral lineage) and divergent (different function, common ancestor) evolution of function are observed. However, a common theme is that a single conserved domain (often the nucleoside triphosphate binding domain) is combined with ancillary domains that provide the variation in substrate binding and function.
    MeSH term(s) Amino Acid Sequence ; Animals ; Catalysis ; Cluster Analysis ; Evolution, Molecular ; Humans ; Ligases/chemistry ; Ligases/classification ; Ligases/physiology ; Protein Structure, Tertiary ; Structure-Activity Relationship
    Chemical Substances Ligases (EC 6.-)
    Language English
    Publishing date 2014-03-21
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2014.03.008
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Co-creation of a complex, multicomponent rehabilitation intervention and feasibility trial protocol for the PostUraL tachycardia Syndrome Exercise (PULSE) study.

    Pearce, Gemma / Holliday, Nikki / Sandhu, Harbinder / Eftekhari, Helen / Bruce, Julie / Timms, Emma / Ablett, Laura / Kavi, Lesley / Simmonds, Jane / Evans, Rebecca / Magee, Paul / Powell, Richard / Keogh, Shane / McGregor, Gordon

    Pilot and feasibility studies

    2023  Volume 9, Issue 1, Page(s) 143

    Abstract: Background: There is a dearth of research to support the treatment of people with postural tachycardia syndrome (PoTS). Despite expert consensus suggesting exercise is recommended for this patient group, there are no randomised control trials examining ... ...

    Abstract Background: There is a dearth of research to support the treatment of people with postural tachycardia syndrome (PoTS). Despite expert consensus suggesting exercise is recommended for this patient group, there are no randomised control trials examining this rigorously. The aim was to co-create a feasibility trial protocol and a rehabilitation intervention for people living with PoTS.
    Methods: The intervention and feasibility trial design were co-created as part of the PostUraL tachycardia Syndrome Exercise (PULSE) study. We used the 'three co's framework' of co-define, co-design and co-refine. Recruitment included key national charities and National Health Service Trusts treating people living with PoTS in the UK. Eighteen patient and public involvement members attended the co-define session, and 16 co-creators with a mix of expertise attended the subsequent co-design and co-refine sessions. Seven intervention practitioners were trained in the rehabilitation intervention, providing feedback for further co-refinement.
    Results: The final co-created intervention comprises online physical activity, and lifestyle and behaviour change support sessions. It is based on functional movement activities using a patient-centred approach tailored to individual needs. Physical activity intensity is guided by individuals' perception of effort rather than by objective measures. Recumbent bikes are provided for home use. Patients deemed randomisation to be acceptable because research in this area was considered important.
    Conclusions: An innovative approach was used to co-create the PULSE intervention and feasibility trial protocol to meet the evidence-based and logistical needs of people living with PoTS, clinicians, service deliverers, third-sector organisations, academics and funders. This can be used as a successful example and template for future research internationally. People living with PoTS were recognised as experts and involved in every aspect of conceptualisation, design and refinement. This complex rehabilitation intervention is currently being tested in a randomised feasibility trial comparing the PULSE intervention with best-practice usual care for people living with PoTS.
    Trial registration: ISRCTN45323485 was registered on April 7, 2020.
    Language English
    Publishing date 2023-08-15
    Publishing country England
    Document type Journal Article
    ZDB-ID 2809935-7
    ISSN 2055-5784
    ISSN 2055-5784
    DOI 10.1186/s40814-023-01365-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: The CoFactor database: organic cofactors in enzyme catalysis.

    Fischer, Julia D / Holliday, Gemma L / Thornton, Janet M

    Bioinformatics (Oxford, England)

    2010  Volume 26, Issue 19, Page(s) 2496–2497

    Abstract: Motivation: Organic enzyme cofactors are involved in many enzyme reactions. Therefore, the analysis of cofactors is crucial to gain a better understanding of enzyme catalysis. To aid this, we have created the CoFactor database.: Results: CoFactor ... ...

    Abstract Motivation: Organic enzyme cofactors are involved in many enzyme reactions. Therefore, the analysis of cofactors is crucial to gain a better understanding of enzyme catalysis. To aid this, we have created the CoFactor database.
    Results: CoFactor provides a web interface to access hand-curated data extracted from the literature on organic enzyme cofactors in biocatalysis, as well as automatically collected information. CoFactor includes information on the conformational and solvent accessibility variation of the enzyme-bound cofactors, as well as mechanistic and structural information about the hosting enzymes.
    Availability: The database is publicly available and can be accessed at http://www.ebi.ac.uk/thornton-srv/databases/CoFactor.
    MeSH term(s) Biocatalysis ; Catalysis ; Coenzymes/chemistry ; Coenzymes/metabolism ; Databases, Factual ; Enzymes/chemistry ; Enzymes/metabolism ; Internet ; Protein Conformation
    Chemical Substances Coenzymes ; Enzymes
    Language English
    Publishing date 2010-08-02
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1422668-6
    ISSN 1367-4811 ; 1367-4803
    ISSN (online) 1367-4811
    ISSN 1367-4803
    DOI 10.1093/bioinformatics/btq442
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Mechanism and Catalytic Site Atlas (M-CSA): a database of enzyme reaction mechanisms and active sites.

    Ribeiro, António J M / Holliday, Gemma L / Furnham, Nicholas / Tyzack, Jonathan D / Ferris, Katherine / Thornton, Janet M

    Nucleic acids research

    2017  Volume 46, Issue D1, Page(s) D618–D623

    Abstract: M-CSA (Mechanism and Catalytic Site Atlas) is a database of enzyme active sites and reaction mechanisms that can be accessed at www.ebi.ac.uk/thornton-srv/m-csa. Our objectives with M-CSA are to provide an open data resource for the community to browse ... ...

    Abstract M-CSA (Mechanism and Catalytic Site Atlas) is a database of enzyme active sites and reaction mechanisms that can be accessed at www.ebi.ac.uk/thornton-srv/m-csa. Our objectives with M-CSA are to provide an open data resource for the community to browse known enzyme reaction mechanisms and catalytic sites, and to use the dataset to understand enzyme function and evolution. M-CSA results from the merging of two existing databases, MACiE (Mechanism, Annotation and Classification in Enzymes), a database of enzyme mechanisms, and CSA (Catalytic Site Atlas), a database of catalytic sites of enzymes. We are releasing M-CSA as a new website and underlying database architecture. At the moment, M-CSA contains 961 entries, 423 of these with detailed mechanism information, and 538 with information on the catalytic site residues only. In total, these cover 81% (195/241) of third level EC numbers with a PDB structure, and 30% (840/2793) of fourth level EC numbers with a PDB structure, out of 6028 in total. By searching for close homologues, we are able to extend M-CSA coverage of PDB and UniProtKB to 51 993 structures and to over five million sequences, respectively, of which about 40% and 30% have a conserved active site.
    MeSH term(s) Biocatalysis ; Catalytic Domain ; Data Curation ; Databases, Protein ; Enzymes/chemistry ; Enzymes/metabolism ; Humans ; Internet ; User-Computer Interface ; Web Browser
    Chemical Substances Enzymes
    Language English
    Publishing date 2017-11-06
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 186809-3
    ISSN 1362-4962 ; 1362-4954 ; 0301-5610 ; 0305-1048
    ISSN (online) 1362-4962 ; 1362-4954
    ISSN 0301-5610 ; 0305-1048
    DOI 10.1093/nar/gkx1012
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: EC-BLAST: a tool to automatically search and compare enzyme reactions.

    Rahman, Syed Asad / Cuesta, Sergio Martinez / Furnham, Nicholas / Holliday, Gemma L / Thornton, Janet M

    Nature methods

    2014  Volume 11, Issue 2, Page(s) 171–174

    Abstract: We present EC-BLAST (http://www.ebi.ac.uk/thornton-srv/software/rbl/), an algorithm and Web tool for quantitative similarity searches between enzyme reactions at three levels: bond change, reaction center and reaction structure similarity. It uses bond ... ...

    Abstract We present EC-BLAST (http://www.ebi.ac.uk/thornton-srv/software/rbl/), an algorithm and Web tool for quantitative similarity searches between enzyme reactions at three levels: bond change, reaction center and reaction structure similarity. It uses bond changes and reaction patterns for all known biochemical reactions derived from atom-atom mapping across each reaction. EC-BLAST has the potential to improve enzyme classification, identify previously uncharacterized or new biochemical transformations, improve the assignment of enzyme function to sequences, and assist in enzyme engineering.
    MeSH term(s) Algorithms ; Animals ; Biochemical Phenomena ; Catalysis ; Databases, Protein ; Enzymes/chemistry ; Enzymes/classification ; Enzymes/metabolism ; Humans ; Internet ; Software
    Chemical Substances Enzymes
    Language English
    Publishing date 2014-01-12
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2169522-2
    ISSN 1548-7105 ; 1548-7091
    ISSN (online) 1548-7105
    ISSN 1548-7091
    DOI 10.1038/nmeth.2803
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Biocuration in the structure-function linkage database: the anatomy of a superfamily.

    Holliday, Gemma L / Brown, Shoshana D / Akiva, Eyal / Mischel, David / Hicks, Michael A / Morris, John H / Huang, Conrad C / Meng, Elaine C / Pegg, Scott C-H / Ferrin, Thomas E / Babbitt, Patricia C

    Database : the journal of biological databases and curation

    2017  Volume 2017

    Language English
    Publishing date 2017-06-12
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S. ; Published Erratum
    ZDB-ID 2496706-3
    ISSN 1758-0463 ; 1758-0463
    ISSN (online) 1758-0463
    ISSN 1758-0463
    DOI 10.1093/database/bax045
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Exploring the Biological and Chemical Complexity of the Ligases

    Holliday, Gemma L / Syed Asad Rahman / Nicholas Furnham / Janet M. Thornton

    Journal of Molecular Biology. 2014 May 15, v. 426

    2014  

    Abstract: Using a novel method to map and cluster chemical reactions, we have re-examined the chemistry of the ligases [Enzyme Commission (EC) Class 6] and their associated protein families in detail. The type of bond formed by the ligase can be automatically ... ...

    Abstract Using a novel method to map and cluster chemical reactions, we have re-examined the chemistry of the ligases [Enzyme Commission (EC) Class 6] and their associated protein families in detail. The type of bond formed by the ligase can be automatically extracted from the equation of the reaction, replicating the EC subclass division. However, this subclass division hides considerable complexities, especially for the C–N forming ligases, which fall into at least three distinct types. The lower levels of the EC classification for ligases are somewhat arbitrary in their definition and add little to understanding their chemistry or evolution. By comparing the multi-domain architecture of the enzymes and using sequence similarity networks, we examined the links between overall reaction and evolution of the ligases. These show that, whilst many enzymes that perform the same overall chemistry group together, both convergent (similar function, different ancestral lineage) and divergent (different function, common ancestor) evolution of function are observed. However, a common theme is that a single conserved domain (often the nucleoside triphosphate binding domain) is combined with ancillary domains that provide the variation in substrate binding and function.
    Keywords chemical reactions ; equations ; evolution ; ligases ; nucleosides ; sequence homology
    Language English
    Dates of publication 2014-0515
    Size p. 2098-2111.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 80229-3
    ISSN 1089-8638 ; 0022-2836
    ISSN (online) 1089-8638
    ISSN 0022-2836
    DOI 10.1016/j.jmb.2014.03.008
    Database NAL-Catalogue (AGRICOLA)

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