Characterization of a Salmonella sugar kinase essential for the utilization of fructose-asparagine

Salmonella can utilize fructose-asparagine (F-Asn), a naturally occurring Amadori product, as its sole carbon and nitrogen source. Conversion of F-Asn to the common intermediates glucose-6-phosphate, aspartate, and ammonia was predicted to involve the sequential action of an asparaginase, a kinase, and a deglycase. Mutants lacking the deglycase are highly attenuated in mouse models of intestinal inflammation owing to the toxic build-up of the deglycase substrate. The limited distribution of this metabolic pathway in the animal gut microbiome raises the prospects for antibacterial discovery. We report the biochemical characterization of the kinase that was expected to transform fructose-aspartate to 6-phosphofructose-aspartate during F-Asn utilization. In addition to confirming its anticipated function, we determined through studies of fructose-aspartate analogues that this kinase exhibits a substrate-specificity with greater tolerance to changes to the amino acid (including the d-isomer of aspartate) than to the sugar.

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Characterization of the Naturally Occurring Oxacillinase of Acinetobacter baumannii

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.49.10.4174-4179.2005 ◽

2005 ◽

Vol 49 (10) ◽

pp. 4174-4179 ◽

Cited By ~ 183

Author(s):

Claire Héritier ◽

Laurent Poirel ◽

Pierre-Edouard Fournier ◽

Jean-Michel Claverie ◽

Didier Raoult ◽

...

Keyword(s):

Amino Acid ◽

Acinetobacter Baumannii ◽

Biochemical Characterization ◽

Amino Acid Identity ◽

Acid Identity ◽

Low Level ◽

Narrow Spectrum ◽

Naturally Occurring

ABSTRACT A chromosomally encoded oxacillinase, OXA-69, was characterized from Acinetobacter baumannii AYE. β-Lactamase OXA-69 shared 97% amino acid identity with the recently described OXA-51 enzyme of A. baumannii and 62 and 56% amino acid identity with the carbapenem-hydrolyzing oxacillinases OXA-24 and OXA-23, respectively. Biochemical characterization of the purified OXA-69 revealed a narrow-spectrum hydrolysis profile but including, at a low level, imipenem and meropenem. By PCR and sequencing bla OXA-69-like genes were identified in all A. baumannii strains tested (n = 12), suggesting that this oxacillinase is naturally occurring in that species.

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Functional and Biochemical Characterization of Immunologically Derived Equine Platelet-Activating Factor

Veterinary Pathology ◽

10.1177/030098588502200413 ◽

1985 ◽

Vol 22 (4) ◽

pp. 375-386 ◽

Cited By ~ 6

Author(s):

H. C. Wimberly ◽

D. O. Slauson ◽

N. R. Neilsen

Keyword(s):

Functional Activity ◽

Biochemical Characterization ◽

Platelet Activating Factor ◽

Biochemical Properties ◽

Naturally Occurring ◽

Rabbit Platelets ◽

Rapid Reaction ◽

Specific Challenge

Antigen-specific challenge of equine leukocytes induced the non-lytic release of a platelet-activating factor in vitro. The equine platelet-activating factor stimulated the release of serotonin from equine platelets in a dose-responsive manner, independent of the presence of cyclo-oxygenase pathway inhibitors such as indomethacin. Rabbit platelets were also responsive to equine platelet-activating factor. The release of equine platelet-activating factor was a rapid reaction with near maximal secretion taking place in 30 seconds. Addition of equine platelet-activating factor to washed equine platelets stimulated platelet aggregation which could not be inhibited by the presence of aspirin or indomethacin. Platelets preincubated with equine platelet-activating factor became specifically desensitized to equine platelet-activating factor while remaining responsive to other platelet stimuli such as collagen and epinephrine. The following biochemical properties of equine platelet-activating factor are identical to those properties of 1-0-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (AGEPC): stability upon exposure to air and acid; loss of functional activity after basecatalyzed methanolysis with subsequent acylation that returned all functional activity; and identical relative mobilities on silica gel G plates developed with chloroform:methanol:water (65:35:6, volume/volume). The combined functional and biochemical characteristics of equine platelet-activating factor strongly suggest identity between this naturally occurring, immunologically derived equine factor and AGEPC.

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Characterization of a Natural, Stable, Reversible and Colourful Anthocyanidin Network from Sphagnum Moss Based Mainly on the Yellow Trans-Chalcone and Red Flavylium Cation Forms

Molecules ◽

10.3390/molecules26030709 ◽

2021 ◽

Vol 26 (3) ◽

pp. 709

Author(s):

Helge Berland ◽

Øyvind M. Andersen

Keyword(s):

Nuclear Magnetic Resonance ◽

Cell Wall ◽

Peat Moss ◽

Sphagnum Moss ◽

Naturally Occurring ◽

Two Component ◽

Colour System ◽

The Common ◽

Cis And Trans

Anthocyanins with various functions in nature are one of the most important sources of colours in plants. They are based on anthocyanidins or 3-deoxyanthocyanidins having in common a C15-skeleton and are unique in terms of how each anthocyanidin is involved in a network of equilibria between different forms exhibiting their own properties including colour. Sphagnorubin C (1) isolated from the cell wall of peat moss (Sphagnum sp.) was in fairly acidic and neutral dimethyl sulfoxide characterized by nuclear magnetic resonance (NMR) and ultraviolet–visible (UV–vis) absorption techniques. At equilibrium, the network of 1 behaved as a two–component colour system involving the reddish flavylium cationic and the yellow trans–chalcone forms. The additional D- and E-rings connected to the common C15-skeleton extend the π-conjugation within the molecule and provide both bathochromic shifts in the absorption spectra of the various forms as well as a low isomerization barrier between the cis- and trans-chalcone forms. The hemiketal and cis-chalcone forms were thus not observed experimentally by NMR due to their short lives. The stable, reversible network of 1 with good colour contrast between its two components has previously not been reported for other natural anthocyanins and might thus have potential in future photochromic systems. This is the first full structural characterization of any naturally occurring anthocyanin chalcone form.

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Biochemical characterization of a glucoamylase from Saccharomycopsis fibuligera R64

Biologia ◽

10.2478/s11756-010-0151-2 ◽

2011 ◽

Vol 66 (1) ◽

Cited By ~ 3

Author(s):

Dessy Natalia ◽

Keni Vidilaseris ◽

Pasjan Satrimafitrah ◽

Wangsa Ismaya ◽

Purkan ◽

...

Keyword(s):

Mass Spectrometry ◽

Amino Acid ◽

Amino Acid Sequence Identity ◽

Biochemical Characterization ◽

Saccharomycopsis Fibuligera ◽

Sequence Identity ◽

Ic50 Value ◽

High Amino Acid ◽

Ph Range

AbstractGlucoamylase from the yeast Saccharomycopsis fibuligera R64 (GLL1) has successfully been purified and characterized. The molecular mass of the enzyme was 56,583 Da as determined by mass spectrometry. The purified enzyme demonstrated optimum activity in the pH range of 5.6–6.4 and at 50°C. The activity of the enzyme was inhibited by acarbose with the IC50 value of 5 μM. GLL1 shares high amino acid sequence identity with GLU1 and GLA1, which are Saccharomycopsis fibuligera glucoamylases from the strains HUT7212 and KZ, respectively. The properties of GLL1, however, resemble that of GLU1. The elucidation of the primary structure of GLL1 contributes to the explanation of this finding.

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UV-induced physiological changes and biochemical characterization of mycosporine-like amino acid in a rice-field cyanobacterium Fischerella sp. strain HKAR-13

South African Journal of Botany ◽

10.1016/j.sajb.2022.01.004 ◽

2022 ◽

Vol 147 ◽

pp. 81-97

Author(s):

Vidya Singh ◽

Jainendra Pathak ◽

Abha Pandey ◽

Haseen Ahmed ◽

Rajneesh ◽

...

Keyword(s):

Amino Acid ◽

Rice Field ◽

Biochemical Characterization ◽

Physiological Changes

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Biochemical characterization of progesterone-induced alterations in bovine uterine fluid amino acid and carbohydrate composition during the conceptus elongation window†

Biology of Reproduction ◽

10.1093/biolre/ioy234 ◽

2018 ◽

Cited By ~ 2

Author(s):

Constantine A Simintiras ◽

José M Sánchez ◽

Michael McDonald ◽

Thiago Martins ◽

Mario Binelli ◽

...

Keyword(s):

Amino Acid ◽

Biochemical Characterization ◽

Carbohydrate Composition ◽

Uterine Fluid

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FIBRINOGEN BIRMINGHAM; A NEW CONGENITAL HETERODIMERIC DYSFIBRINOGENEMIA WITH DEFECTIVE FIBRINOPEPTIDE A RELEASE (Aα 16 Arg→His)

10.1055/s-0038-1643338 ◽

1987 ◽

Author(s):

K R Siebenlist ◽

J T Prchal ◽

M W Masesson

Keyword(s):

Amino Acid ◽

Amino Acid Analysis ◽

Hplc Analysis ◽

Biochemical Characterization ◽

Clinical Manifestations ◽

Severe Bleeding ◽

Fibrinopeptide A ◽

History Of ◽

Bleeding Episodes

Aα 16 Arg→His substitutions are common forms of congenital dysfibrinogenemias. Clinical manifestations range from asymptomatic to moderate hemorrhagic tendencies. Biochemical characterization of one such heterozygotic individual (Fibrinogen Louisville, Galanakis, etal. Ann NY Acad Sci 408:644,1983) indicated that only homodimeric fibrinogen molecules (i.e., containing either normal or abnormal Aα chains) were present. We isolated fibrinogen from the plasma of a 23 year old patient with a history of easy bruising and several recent moderate to severe bleeding episodes. Coagulability with reptilase was 677 (65-70%; n=5) whereas with thrombin (Ha) it approached 100%, depending directly upon the time of incubation with enzyme. HPLC analysis of Ila-induced fibrinopeptide release demonstrated the presence of an abnormal A-peptide (A*), amounting to 50% of the total, which was released more slowly than the normal A-peptide (A). Amino acid analysis of A* demonstrated the absence of Arg and the presence of His. Carboxypeptidase digestion confirmed the structure of A* as Aα 16 Arg-→ His. The clot and the soluble clot liquor resulting from reptilase treatment were separated and each was then further treated with Ilato release A*. HPLC analysis indicated that 31% of the total A* present in the sample was associated with the reptilase clot and 697 remained in the clot liquor. This distribution of A* suggests that Fibrinogen Birmingham, unlike Fibrinogen Louisville, contains heterodimeric molecules that are incorporated into the reptilase clottable fraction. This finding is consistent with a process of random hepatic assembly of dimeric fibrinogen molecules in a heterozygotic individual.

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Biochemical characterization of a second family of human Ia molecules, HLA-DS, equivalent to murine I-A subregion molecules.

Journal of Experimental Medicine ◽

10.1084/jem.156.2.550 ◽

1982 ◽

Vol 156 (2) ◽

pp. 550-566 ◽

Cited By ~ 145

Author(s):

S M Goyert ◽

J E Shively ◽

J Silver

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Amino Acid Sequence Identity ◽

Biochemical Characterization ◽

Amino Acid Sequence Homology ◽

Molecular Weights ◽

Hla Dr ◽

D Region ◽

Polypeptide Chains

In mice, two families of structurally distinct Ia molecules, one designated I-A and the other I-E, have been identified and characterized. The HLA-DR molecules represent one family of human Ia molecules equivalent to the murine I-E molecules on the basis of amino acid sequence homology. We describe the isolation and biochemical characterization of a second family of human Ia molecules, designated HLA-DS for second D-region locus, equivalent to the murine I-A molecules. The human HLA-DS molecules consist of two polypeptide chains, DS alpha (37,000 mol wt) and DS beta (29,000 mol wt), with 73% amino acid sequence identity to the murine I-A molecules. Furthermore, the HLA-DS molecules are closely linked genetically to HLA-DR molecules, a situation analogous to that observed in mice. The similarity in molecular weights of the DR and DS molecules might explain why others have failed to identify the latter in man.

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Thrombin A-Chain: Activation Remnant or Allosteric Effector?

Thrombosis ◽

10.1155/2010/416167 ◽

2010 ◽

Vol 2010 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Isis S. R. Carter ◽

Amanda L. Vanden Hoek ◽

Edward L. G. Pryzdial ◽

Ross T. A. MacGillivray

Keyword(s):

Biochemical Characterization ◽

Catalytic Domain ◽

Current Data ◽

Enzymatic Reactions ◽

Allosteric Effector ◽

Naturally Occurring ◽

Physiologic Function ◽

A Chain

Although prothrombin is one of the most widely studied enzymes in biology, the role of the thrombin A-chain has been neglected in comparison to the other domains. This paper summarizes the current data on the prothrombin catalytic domain A-chain region and the subsequent thrombin A-chain. Attention is given to biochemical characterization of naturally occurring prothrombin A-chain mutations and alanine scanning mutants in this region. While originally considered to be simply an activation remnant with little physiologic function, the thrombin A-chain is now thought to play a role as an allosteric effector in enzymatic reactions and may also be a structural scaffold to stabilize the protease domain.

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