Search Results - "Ludwig, Martha L"

Cobalamin-independent methionine synthase (MetE): a face-to-face double barrel that evolved by gene duplication by Pejchal, Robert, Ludwig, Martha L

“…Cobalamin-independent methionine synthase (MetE) catalyzes the transfer of a methyl group from methyltetrahydrofolate to L-homocysteine (Hcy) without using an…”
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Metal active site elasticity linked to activation of homocysteine in methionine synthases by Koutmos, Markos, Pejchal, Robert, Bomer, Theresa M, Matthews, Rowena G, Smith, Janet L, Ludwig, Martha L

“…Enzymes possessing catalytic zinc centers perform a variety of fundamental processes in nature, including methyl transfer to thiols. Cobalamin-independent…”
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disulfide-stabilized conformer of methionine synthase reveals an unexpected role for the histidine ligand of the cobalamin cofactor by Datta, Supratim, Koutmos, Markos, Pattridge, Katherine A, Ludwig, Martha L, Matthews, Rowena G

“…B₁₂-dependent methionine synthase (MetH) from Escherichia coli is a large modular protein that is alternately methylated by methyltetrahydrofolate to form…”
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Structures of the N-Terminal Modules Imply Large Domain Motions during Catalysis by Methionine Synthase by Evans, John C, Huddler, Donald P, Hilgers, Mark T, Romanchuk, Gail, Matthews, Rowena G, Ludwig, Martha L

“…B12-dependent methionine synthase (MetH) is a large modular enzyme that utilizes the cobalamin cofactor as a methyl donor or acceptor in three separate…”
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Structural Perturbations in the Ala → Val Polymorphism of Methylenetetrahydrofolate Reductase:  How Binding of Folates May Protect against Inactivation by Pejchal, Robert, Campbell, Elizabeth, Guenther, Brian D, Lennon, Brett W, Matthews, Rowena G, Ludwig, Martha L

“…In human methylenetetrahydrofolate reductase (MTHFR) the Ala222Val (677C→T) polymorphism encodes a heat-labile gene product that is associated with elevated…”
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Crystal Structure of the Quorum-Sensing Protein LuxS Reveals a Catalytic Metal Site by Hilgers, Mark T., Ludwig, Martha L.

“…The ability of bacteria to regulate gene expression in response to changes in cell density is termed quorum sensing. This behavior involves the synthesis and…”
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STRUCTURE-BASED PERSPECTIVES ON B12-DEPENDENT ENZYMES by Ludwig and, Martha L, Matthews, Rowena G

“…Two X-ray structures of cobalamin (B 12 ) bound to proteins have now been determined. These structures reveal that the B 12 cofactor undergoes a major…”
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Factors Modulating Conformational Equilibria in Large Modular Proteins: A Case Study with Cobalamin-Dependent Methionine Synthase by Bandarian, Vahe, Ludwig, Martha L., Matthews, Rowena G.

“…In the course of catalysis or signaling, large multimodular proteins often undergo conformational changes that reposition the modules with respect to one…”
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Domain alternation switches B12-dependent methionine synthase to the activation conformation by Barian, Vahe, Pattridge, Katherine A., Lennon, Brett W., Huddler, Donald P., Matthews, Rowena G., Ludwig, Martha L.

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A prototypical cytidylyltransferase: CTP:glycerol-3-phosphate cytidylyltransferase from Bacillus subtilis by Weber, Christian H, Park, Young Seo, Sanker, Subramaniam, Kent, Claudia, Ludwig, Martha L

“…Background: The formation of critical intermediates in the biosynthesis of lipids and complex carbohydrates is carried out by cytidylyltransferases, which…”
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Control of Oxidation−Reduction Potentials in Flavodoxin from Clostridium beijerinckii:  The Role of Conformation Changes by Ludwig, Martha L, Pattridge, Katherine A, Metzger, Anita L, Dixon, Melinda M, Eren, Mesut, Feng, Yucheng, Swenson, Richard P

“…X-ray analyses of wild-type and mutant flavodoxins from Clostridium beijerinckii show that the conformation of the peptide Gly57-Asp58, in a bend near the…”
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The structure and properties of methylenetetrahydrofolate reductase from Escherichia coli suggest how folate ameliorates human hyperhomocysteinemia by Guenther, Brian D, Ludwig, Martha L, Matthews, Rowena G, Rozen, Rima, Tran, Pamela, Sheppard, Christal A

“…Elevated plasma homocysteine levels are associated with increased risk for cardiovascular disease and neural tube defects in humans. Folate treatment decreases…”
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Phthalate Dioxygenase Reductase: A Modular Structure for Electron Transfer from Pyridine Nucleotides to [2Fe-2S] by Correll, Carl C., Batie, Christopher J., Ballou, David P., Ludwig, Martha L.

“…Phthalate dioxygenase reductase (PDR) is a prototypical iron-sulfur flavoprotein (36 kilodaltons) that utilizes flavin mononucleotide (FMN) to mediate electron…”
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The Mobile Flavin of 4-OH Benzoate Hydroxylase by Gatti, Domenico L., Palfey, Bruce A., Lah, Myoung Soo, Entsch, Barrie, Massey, Vincent, Ballou, David P., Ludwig, Martha L.

“…Para-hydroxybenzoate hydroxylase inserts oxygen into substrates by means of the labile intermediate, flavin C(4a)-hydroperoxide. This reaction requires…”
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Structures of NADH and CH3-H4Folate Complexes of Escherichia coli Methylenetetrahydrofolate Reductase Reveal a Spartan Strategy for a Ping-Pong Reaction by Pejchal, Robert, Sargeant, Ryan, Ludwig, Martha L

“…Methylenetetrahydrofolate reductases (MTHFRs; EC 1.7.99.5) catalyze the NAD(P)H-dependent reduction of 5,10-methylenetetrahydrofolate (CH2-H4folate) to…”
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Folate Activation and Catalysis in Methylenetetrahydrofolate Reductase from Escherichia coli:  Roles for Aspartate 120 and Glutamate 28 by Trimmer, Elizabeth E, Ballou, David P, Ludwig, Martha L, Matthews, Rowena G

“…The flavoprotein Escherichia coli methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of 5,10-methylenetetrahydrofolate (CH2-H4folate) to…”
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Mutations in the B12-Binding Region of Methionine Synthase:  How the Protein Controls Methylcobalamin Reactivity by Jarrett, Joseph T, Amaratunga, Mohan, Drennan, Catherine L, Scholten, Jeffrey D, Sands, Richard H, Ludwig, Martha L, Matthews, Rowena G

“…Vitamin B12-dependent methionine synthase catalyzes the transfer of a methyl group from methyltetrahydrofolate to homocysteine via the enzyme-bound cofactor…”
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X-ray Absorption Spectroscopy of the Iron Site in Escherichia coli Fe(III) Superoxide Dismutase by Tierney, David L, Fee, James A, Ludwig, Martha L, Penner-Hahn, James E

“…The local structure of the iron site in ferric superoxide dismutase from Escherichia coli has been characterized by X-ray absorption spectroscopy. In the…”
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Twists in Catalysis: Alternating Conformations of Escherichia coli Thioredoxin Reductase by Lennon, Brett W., Williams, Charles H., Ludwig, Martha L.

“…In thioredoxin reductase (TrxR) from Escherichia coli, cycles of reduction and reoxidation of the flavin adenine dinucleotide (FAD) cofactor depend on…”
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pH-Dependent Structural Changes in the Active Site of p-Hydroxybenzoate Hydroxylase Point to the Importance of Proton and Water Movements during Catalysis by Gatti, Domenico L, Entsch, Barrie, Ballou, David P, Ludwig, Martha L

“…Deprotonation of p-hydroxybenzoate to the phenolate and reprotonation of the hydroxylated dienone intermediate to form the product are essential steps in the…”
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