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  1. Article ; Online: Simulated digestions of free oligosaccharides and mucin-type O-glycans reveal a potential role for Clostridium perfringens.

    McDonald, Andrew G / Lisacek, Frédérique

    Scientific reports

    2024  Volume 14, Issue 1, Page(s) 1649

    Abstract: The development of a stable human gut microbiota occurs within the first year of life. Many open questions remain about how microfloral species are influenced by the composition of milk, in particular its content of human milk oligosaccharides (HMOs). ... ...

    Abstract The development of a stable human gut microbiota occurs within the first year of life. Many open questions remain about how microfloral species are influenced by the composition of milk, in particular its content of human milk oligosaccharides (HMOs). The objective is to investigate the effect of the human HMO glycome on bacterial symbiosis and competition, based on the glycoside hydrolase (GH) enzyme activities known to be present in microbial species. We extracted from UniProt a list of all bacterial species catalysing glycoside hydrolase activities (EC 3.2.1.-), cross-referencing with the BRENDA database, and obtained a set of taxonomic lineages and CAZy family data. A set of 13 documented enzyme activities was selected and modelled within an enzyme simulator according to a method described previously in the context of biosynthesis. A diverse population of experimentally observed HMOs was fed to the simulator, and the enzymes matching specific bacterial species were recorded, based on their appearance of individual enzymes in the UniProt dataset. Pairs of bacterial species were identified that possessed complementary enzyme profiles enabling the digestion of the HMO glycome, from which potential symbioses could be inferred. Conversely, bacterial species having similar GH enzyme profiles were considered likely to be in competition for the same set of dietary HMOs within the gut of the newborn. We generated a set of putative biodegradative networks from the simulator output, which provides a visualisation of the ability of organisms to digest HMO and mucin-type O-glycans. B. bifidum, B. longum and C. perfringens species were predicted to have the most diverse GH activity and therefore to excel in their ability to digest these substrates. The expected cooperative role of Bifidobacteriales contrasts with the surprising capacities of the pathogen. These findings indicate that potential pathogens may associate in human gut based on their shared glycoside hydrolase digestive apparatus, and which, in the event of colonisation, might result in dysbiosis. The methods described can readily be adapted to other enzyme categories and species as well as being easily fine-tuneable if new degrading enzymes are identified and require inclusion in the model.
    MeSH term(s) Infant, Newborn ; Humans ; Clostridium perfringens ; Bifidobacterium ; Mucins/analysis ; Oligosaccharides/analysis ; Milk, Human/chemistry ; Bifidobacterium bifidum ; Bacteria ; Glycoside Hydrolases/analysis ; Digestion
    Chemical Substances Mucins ; Oligosaccharides ; Glycoside Hydrolases (EC 3.2.1.-)
    Language English
    Publishing date 2024-01-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-023-51012-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Enzyme nomenclature and classification: the state of the art

    McDonald, Andrew G. / Tipton, Keith F.

    The FEBS Journal. 2023 May, v. 290, no. 9 p.2214-2231

    2023  

    Abstract: The IUBMB enzyme classification system, available at the IUBMB ExplorEnz website, uses a four‐component number (the EC number) that identifies an enzyme in terms of reaction catalysed. There were originally six recognized groups of enzymes: ... ...

    Abstract The IUBMB enzyme classification system, available at the IUBMB ExplorEnz website, uses a four‐component number (the EC number) that identifies an enzyme in terms of reaction catalysed. There were originally six recognized groups of enzymes: Oxidoreductases (EC 1), Transferases (EC 2), Hydrolases (EC 3), Lyases (EC 4), Isomerases (EC 5) and Ligases (EC 6). Of these, the lyases, which are defined as ‘enzymes that cleave C‐C, C‐O, C‐N and other bonds by means other than by hydrolysis or oxidation’, present particular recognition and classification problems. Recently, a new class, the Translocases (EC 7), has been added, which incorporates enzymes that catalyse the movement of ions or molecules across membranes or their separation within membranes. A new subclass of the isomerases has also been included for those enzymes that alter the conformations of proteins and nucleic acids. Newly reported enzymes are being regularly added to the list after validation and where new information affects the classification of an existing entry, a new EC number is created, but the old one is not reused.
    Keywords Internet ; hydrolases ; hydrolysis ; isomerases ; ligases ; lyases ; oxidation ; oxidoreductases ; transferases
    Language English
    Dates of publication 2023-05
    Size p. 2214-2231.
    Publishing place John Wiley & Sons, Ltd
    Document type Article ; Online
    Note REVIEW
    ZDB-ID 2173655-8
    ISSN 1742-4658 ; 1742-464X
    ISSN (online) 1742-4658
    ISSN 1742-464X
    DOI 10.1111/febs.16274
    Database NAL-Catalogue (AGRICOLA)

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  3. Article ; Online: Parameter Reliability and Understanding Enzyme Function.

    McDonald, Andrew G / Tipton, Keith F

    Molecules (Basel, Switzerland)

    2022  Volume 27, Issue 1

    Abstract: Knowledge of the Michaelis-Menten parameters and their meaning in different circumstances is an essential prerequisite to understanding enzyme function and behaviour. The published literature contains an abundance of values reported for many enzymes. The ...

    Abstract Knowledge of the Michaelis-Menten parameters and their meaning in different circumstances is an essential prerequisite to understanding enzyme function and behaviour. The published literature contains an abundance of values reported for many enzymes. The problem concerns assessing the appropriateness and validity of such material for the purpose to which it is to be applied. This review considers the evaluation of such data with particular emphasis on the assessment of its fitness for purpose.
    MeSH term(s) Algorithms ; Enzymes/chemistry ; Models, Chemical
    Chemical Substances Enzymes
    Language English
    Publishing date 2022-01-01
    Publishing country Switzerland
    Document type Journal Article ; Review
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules27010263
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Enzyme nomenclature and classification: the state of the art.

    McDonald, Andrew G / Tipton, Keith F

    The FEBS journal

    2022  Volume 290, Issue 9, Page(s) 2214–2231

    Abstract: The IUBMB enzyme classification system, available at the IUBMB ExplorEnz website, uses a four-component number (the EC number) that identifies an enzyme in terms of reaction catalysed. There were originally six recognized groups of enzymes: ... ...

    Abstract The IUBMB enzyme classification system, available at the IUBMB ExplorEnz website, uses a four-component number (the EC number) that identifies an enzyme in terms of reaction catalysed. There were originally six recognized groups of enzymes: Oxidoreductases (EC 1), Transferases (EC 2), Hydrolases (EC 3), Lyases (EC 4), Isomerases (EC 5) and Ligases (EC 6). Of these, the lyases, which are defined as 'enzymes that cleave C-C, C-O, C-N and other bonds by means other than by hydrolysis or oxidation', present particular recognition and classification problems. Recently, a new class, the Translocases (EC 7), has been added, which incorporates enzymes that catalyse the movement of ions or molecules across membranes or their separation within membranes. A new subclass of the isomerases has also been included for those enzymes that alter the conformations of proteins and nucleic acids. Newly reported enzymes are being regularly added to the list after validation and where new information affects the classification of an existing entry, a new EC number is created, but the old one is not reused.
    MeSH term(s) Oxidoreductases ; Isomerases ; Transferases ; Lyases ; Hydrolases ; Ligases ; Enzymes/chemistry
    Chemical Substances Oxidoreductases (EC 1.-) ; Isomerases (EC 5.-) ; Transferases (EC 2.-) ; Lyases (EC 4.-) ; Hydrolases (EC 3.-) ; Ligases (EC 6.-) ; Enzymes
    Language English
    Publishing date 2022-01-03
    Publishing country England
    Document type Journal Article ; Review
    ZDB-ID 2173655-8
    ISSN 1742-4658 ; 1742-464X
    ISSN (online) 1742-4658
    ISSN 1742-464X
    DOI 10.1111/febs.16274
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Parameter Reliability and Understanding Enzyme Function

    Andrew G. McDonald / Keith F. Tipton

    Molecules, Vol 27, Iss 263, p

    2022  Volume 263

    Abstract: Knowledge of the Michaelis–Menten parameters and their meaning in different circumstances is an essential prerequisite to understanding enzyme function and behaviour. The published literature contains an abundance of values reported for many enzymes. The ...

    Abstract Knowledge of the Michaelis–Menten parameters and their meaning in different circumstances is an essential prerequisite to understanding enzyme function and behaviour. The published literature contains an abundance of values reported for many enzymes. The problem concerns assessing the appropriateness and validity of such material for the purpose to which it is to be applied. This review considers the evaluation of such data with particular emphasis on the assessment of its fitness for purpose.
    Keywords enzyme kinetics ; Michaelis constant ; maximal velocity ; substrate competition ; enzyme inhibition ; cooperativity ; Organic chemistry ; QD241-441
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: First remains of the enormous alligatoroid

    Mohler, Benjamin F / McDonald, Andrew T / Wolfe, Douglas G

    PeerJ

    2021  Volume 9, Page(s) e11302

    Abstract: ... The ... ...

    Abstract The neosuchian
    Language English
    Publishing date 2021-04-21
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2703241-3
    ISSN 2167-8359
    ISSN 2167-8359
    DOI 10.7717/peerj.11302
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Allocated but not treated: the silent 16.

    Lee, Todd C / Morris, Andrew M / Schwartz, Ilan S / McDonald, Emily G

    Lancet (London, England)

    2022  Volume 399, Issue 10337, Page(s) 1775

    MeSH term(s) Humans ; Intracranial Aneurysm ; Magnetic Resonance Angiography
    Language English
    Publishing date 2022-05-05
    Publishing country England
    Document type Letter ; Comment
    ZDB-ID 3306-6
    ISSN 1474-547X ; 0023-7507 ; 0140-6736
    ISSN (online) 1474-547X
    ISSN 0023-7507 ; 0140-6736
    DOI 10.1016/S0140-6736(22)00377-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Simulating the enzymes of ganglioside biosynthesis with Glycologue.

    McDonald, Andrew G / Davey, Gavin P

    Beilstein journal of organic chemistry

    2021  Volume 17, Page(s) 739–748

    Abstract: Gangliosides are an important class of sialylated glycosphingolipids linked to ceramide that are a component of the mammalian cell surface, especially those of the central nervous system, where they function in intercellular recognition and communication. ...

    Abstract Gangliosides are an important class of sialylated glycosphingolipids linked to ceramide that are a component of the mammalian cell surface, especially those of the central nervous system, where they function in intercellular recognition and communication. We describe an in silico method for determining the metabolic pathways leading to the most common gangliosides, based on the known enzymes of their biosynthesis. A network of 41 glycolipids is produced by the actions of the 10 enzymes included in the model. The different ganglioside nomenclature systems in common use are compared and a systematic variant of the widely used Svennerholm nomenclature is described. Knockouts of specific enzyme activities are used to simulate congenital defects in ganglioside biosynthesis, and altered ganglioside status in cancer, and the effects on network structure are predicted. The simulator is available at the Glycologue website, https://glycologue.org/.
    Language English
    Publishing date 2021-03-23
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 2192461-2
    ISSN 1860-5397
    ISSN 1860-5397
    DOI 10.3762/bjoc.17.64
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: O-Glycologue: A Formal-Language-Based Generator of O-Glycosylation Networks.

    McDonald, Andrew G / Davey, Gavin P

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

    2021  Volume 2370, Page(s) 223–236

    Abstract: The web application O-Glycologue provides an online simulation of the biosynthetic enzymes of O-linked glycosylation, using a knowledge-based system described previously. Glycans can be imported in GlycoCT condensed format, or else as IUPAC condensed ... ...

    Abstract The web application O-Glycologue provides an online simulation of the biosynthetic enzymes of O-linked glycosylation, using a knowledge-based system described previously. Glycans can be imported in GlycoCT condensed format, or else as IUPAC condensed names, and passed as substrates to the enzymes, which are modeled as regular-expression-based substitutions on strings. The resulting networks of reactions can be exported as SBML. The effects of knocking out different sets of enzyme activities can be compared. A method is provided for predicting the enzymes required to produce a given substrate, using an O-glycan from human gastric mucin as an example. The system has been adapted to other systems of glycosylation enzymes, and an application to ganglioside oligosaccharide synthesis is demonstrated. O-Glycologue is available at https://glycologue.org/o/ .
    MeSH term(s) Glycosylation ; Humans ; Language ; Oligosaccharides ; Polysaccharides ; Software
    Chemical Substances Oligosaccharides ; Polysaccharides
    Language English
    Publishing date 2021-10-05
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1940-6029
    ISSN (online) 1940-6029
    DOI 10.1007/978-1-0716-1685-7_11
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: In silico analysis of the human milk oligosaccharide glycome reveals key enzymes of their biosynthesis.

    McDonald, Andrew G / Mariethoz, Julien / Davey, Gavin P / Lisacek, Frédérique

    Scientific reports

    2022  Volume 12, Issue 1, Page(s) 10846

    Abstract: Human milk oligosaccharides (HMOs) form the third most abundant component of human milk and are known to convey several benefits to the neonate, including protection from viral and bacterial pathogens, training of the immune system, and influencing the ... ...

    Abstract Human milk oligosaccharides (HMOs) form the third most abundant component of human milk and are known to convey several benefits to the neonate, including protection from viral and bacterial pathogens, training of the immune system, and influencing the gut microbiome. As HMO production during lactation is driven by enzymes that are common to other glycosylation processes, we adapted a model of mucin-type GalNAc-linked glycosylation enzymes to act on free lactose. We identified a subset of 11 enzyme activities that can account for 206 of 226 distinct HMOs isolated from human milk and constructed a biosynthetic reaction network that identifies 5 new core HMO structures. A comparison of monosaccharide compositions demonstrated that the model was able to discriminate between two possible groups of intermediates between major subnetworks, and to assign possible structures to several previously uncharacterised HMOs. The effect of enzyme knockouts is presented, identifying β-1,4-galactosyltransferase and β-1,3-N-acetylglucosaminyltransferase as key enzyme activities involved in the generation of the observed HMO glycosylation patterns. The model also provides a synthesis chassis for the most common HMOs found in lactating mothers.
    MeSH term(s) Bacteria ; Female ; Gastrointestinal Microbiome ; Humans ; Infant, Newborn ; Lactation ; Milk, Human/chemistry ; Oligosaccharides/chemistry
    Chemical Substances Oligosaccharides
    Language English
    Publishing date 2022-06-27
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-022-14260-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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