Purification and partial characterization of an antibiotic produced by Myxococcus xanthus

1974 ◽  
Vol 20 (2) ◽  
pp. 155-161 ◽  
Author(s):  
B. Vaks ◽  
A. Zuckerberg ◽  
E. Rosenberg
Keyword(s):  
Mass Spectra ◽  
Protein Hydrolysate ◽  
Antibiotic Production ◽  
Myxococcus Xanthus ◽  
Chromatographic Behavior ◽  
Gram Negative Bacteria ◽  
Apparent Homogeneity ◽  
Silicic Acid Chromatography ◽  
Solvent Systems

A strain of Myxococcus xanthus, referred to as M. xanthus TA, has been isolated which produces an antibiotic capable of inhibiting growth of certain Gram-positive and Gram-negative bacteria. Antibiotic production was significantly inhibited when the concentration of protein hydrolysate in the production medium exceeded 1%. The antibiotic was purified over 1000 times to apparent homogeneity by silicic acid chromatography and by a variety of preparative alumina thin-layer chromatographic procedures. The purified antibiotic was partially characterized by its chromatographic behavior in six solvent systems, stability to acid, alkali and heat, infrared, ultraviolet, and mass spectra. The antibiotic has a λmax of 242 nm in methanol.

scholarly journals Virulence and Prodigiosin Antibiotic Biosynthesis in Serratia Are Regulated Pleiotropically by the GGDEF/EAL Domain Protein, PigX

2007 ◽  
Vol 189 (21) ◽  
pp. 7653-7662 ◽  
Author(s):  
Peter C. Fineran ◽  
Neil R. Williamson ◽  
Kathryn S. Lilley ◽  
George P. C. Salmond
Keyword(s):  
Plant Cell Wall ◽  
Antibiotic Production ◽  
Transcriptional Start Site ◽  
Antibiotic Biosynthesis ◽  
Gram Negative Bacteria ◽  
Cell Wall Degrading Enzymes ◽  
Insect Pathogens ◽  
Domain Protein ◽  
Pectinase Production

ABSTRACT Gram-negative bacteria of the genus Serratia are opportunistic human, plant, and insect pathogens. Serratia sp. strain ATCC 39006 secretes pectinases and cellulases and produces the secondary metabolites carbapenem and prodigiosin. Mutation of a gene (pigX) resulted in an extremely pleiotropic phenotype: prodigiosin antibiotic biosynthesis, plant virulence, and pectinase production were all elevated. PigX controlled secondary metabolism by repressing the transcription of the target prodigiosin biosynthetic operon (pigA-pigO). The transcriptional start site of pigX was determined, and pigX expression occurred in parallel with Pig production. Detailed quantitative intracellular proteome analyses enabled the identification of numerous downstream targets of PigX, including OpgG, mutation of which reduced the production of the plant cell wall-degrading enzymes and virulence. The highly pleiotropic PigX regulator contains GGDEF and EAL domains with noncanonical motifs and is predicted to be membrane associated. Genetic evidence suggests that PigX might function as a cyclic dimeric GMP phosphodiesterase. This is the first characterization of a GGDEF and EAL domain protein in Serratia and the first example of the regulation of antibiotic production by a GGDEF/EAL domain protein.

Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Human Urine ◽  
Gel Filtration ◽  
Chain Structure ◽  
The Other ◽  
Single Chain ◽  
Apparent Homogeneity ◽  
Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

Electrophysiological Characterization of Transport Across Outer Membrane Channels from Gram-Negative Bacteria in Their Native Environment

2019 ◽  
Author(s):  
Jiajun Wang ◽  
Rémi Terrasse ◽  
Jayesh Arun Bafna ◽  
Lorraine Benier ◽  
Mathias Winterhalter
Keyword(s):  
Outer Membrane ◽  
Lipid Membrane ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Multi Drug Resistance ◽  
Gram Negative Bacteria ◽  
Membrane Channels ◽  
Gram Negative ◽  
Electrophysiological Characterization

Multi-drug resistance in Gram-negative bacteria is often associated with low permeability of the outer membrane. To investigate the role of membrane channels in the uptake of antibiotics, we extract, purify and reconstitute them into artificial planar membranes. To avoid this time-consuming procedure, here we show a robust approach using fusion of native outer membrane vesicles (OMV) into planar lipid bilayer which moreover allows also to some extend the characterization of membrane protein channels in their native environment. Two major membrane channels from <i>Escherichia coli</i>, OmpF and OmpC, were overexpressed from the host and the corresponding OMVs were collected. Each OMV fusion revealed surprisingly single or only few channel activities. The asymmetry of the OMV´s translates after fusion into the lipid membrane with the LPS dominantly present at the side of OMV addition. Compared to conventional reconstitution methods, the channels fused from OMVs containing LPS have similar conductance but a much broader distribution. The addition of Enrofloxacin on the LPS side yields somewhat higher association (<i>k<sub>on</sub></i>) and lower dissociation (<i>k<sub>off</sub></i>) rates compared to LPS-free reconstitution. We conclude that using outer membrane vesicles is a fast and easy approach for functional and structural studies of membrane channels in the native membrane.

Synthesis and Characterization of Potential and Degraded Impurities of Regadenoson

2020 ◽  
Vol 16 (8) ◽  
pp. 1130-1139
Author(s):  
Singaram Sathiyanarayanan ◽  
Chidambaram Subramanian Venkatesan ◽  
Senthamaraikannan Kabilan
Keyword(s):  
Mass Spectra ◽  
Degradation Products ◽  
Hplc Method ◽  
Forced Degradation ◽  
Spectroscopic Techniques ◽  
A2a Adenosine Receptor ◽  
Degradation Study ◽  
Related Substances ◽  
Adenosine Receptor Agonist

Background: Regadenoson is an A2A adenosine receptor agonist that is a coronary vasodilator and commonly used as a pharmacologic cardiac stressing agents. Methods: HPLC method was used for the analysis of related substances. The degraded impurities during the process were isolated and characterized by IR, Mass and NMR spectral analysis. Results: Forced degradation study of regadenoson under conditions of hydrolysis (neutral, acidic and alkaline) and oxidations suggested in the ICH Q1A(R2) was accomplished. The drug showed significant degradation under all the above conditions. On the whole, five novel degradation products were found under diverse conditions along with process related impurities which were not reported earlier. Conclusion: All the degradation products were well characterized by using advanced spectroscopic techniques like IR, 1H NMR, 13C NMR and Mass spectra. The identification of these impurities will be productive for the quality control during the production and stability behavior of the regadenoson drug substance.

scholarly journals Synthesis, Characterization of Chitosan-Aluminum Oxide Nanocomposite for Green Synthesis of Annulated Imidazopyrazol Thione Derivatives

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1160
Author(s):  
Abir S. Abdel-Naby ◽  
Sara Nabil ◽  
Sarah Aldulaijan ◽  
Ibtisam M. Ababutain ◽  
Azzah I. Alghamdi ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Aluminum Oxide ◽  
Reaction Medium ◽  
Thiol Group ◽  
Docking Studies ◽  
Significant Loss ◽  
Gram Negative Bacteria ◽  
Organic Catalyst ◽  
Group 1

Chitosan-aluminum oxide nanocomposite was synthesized, characterized, and used as a green heterogeneous catalyst to synthesize novel imidazopyrazolylthione derivatives. Nanocomposite polymeric material was characterized by EDS-SEM and XRD. The powerful catalytic activity, and its base character of the nanocomposite, was used to synthesize imidazopyrazolylthione (1) in a good yield compared to traditional cyclocondensation synthesis. Using the nanocomposite catalyst, substitution of the thiol group (1) afforded the corresponding thiourea (2) and the corresponding ester (3). The efficiency of the nanocomposite over the traditional base organic catalyst, Et3N and NaOH, makes it an effective, economic, and reproducible nontoxic catalyst. Moreover, the heterogeneous nanocomposite polymeric film was easily isolated from the reaction medium, and recycled up to four times, without a significant loss of its catalytic activity. The newly synthesized derivatives were screened as antibacterial agents and showed high potency. Molecular docking was also performed for a more in-depth investigation. The results of the docking studies have demonstrated that the docked compounds have strong interaction energies with both Gram-positive and Gram-negative bacteria.

scholarly journals Discovery and Characterization of the Antimetabolite Action of Thioacetamide-Linked 1,2,3-Triazoles as Disruptors of Cysteine Biosynthesis in Gram-Negative Bacteria

2019 ◽  
Vol 6 (3) ◽  
pp. 467-478 ◽  
Author(s):  
Miranda J. Wallace ◽  
Suresh Dharuman ◽  
Dinesh M. Fernando ◽  
Stephanie M. Reeve ◽  
Clifford T. Gee ◽  
...  
Keyword(s):  
Gram Negative Bacteria ◽  
Cysteine Biosynthesis ◽  
Gram Negative

Synthesis and Characterization of Tris(trimethyltin) Thiophosphate (Me3Sn)3PO3S

1993 ◽  
Vol 48 (12) ◽  
pp. 1781-1783 ◽  
Author(s):  
Abdel-Fattah Shihada
Keyword(s):  
Aqueous Medium ◽  
Raman Spectra ◽  
Mass Spectra ◽  
Ir And Raman Spectra ◽  
Synthesis And Characterization ◽  
Polymeric Structure ◽  
Ir And Raman

(Me3Sn)3PO3S has been prepared from the reaction of Me3SnCl with Na3PO3S • 12 H2O under cooling in aqueous medium. Its IR and Raman spectra are found to be consistent with a polymeric structure with tetra- and penta-coordinated tin atoms. The 31P NMR and mass spectra of (Me3Sn)3PO3S are reported and discussed.

scholarly journals Occurrence of fatty acid epoxide hydrolases in soybean (Glycine max). Purification and characterization of the soluble form

1992 ◽  
Vol 282 (3) ◽  
pp. 711-714 ◽  
Author(s):  
E Blée ◽  
F Schuber
Keyword(s):  
Glycine Max ◽  
Gel Filtration ◽  
Soluble Form ◽  
Soluble Enzyme ◽  
Purification And Characterization ◽  
Epoxide Hydrolases ◽  
Major Activity ◽  
Apparent Homogeneity ◽  
A Minor

Epoxide hydrolases catalysing the hydration of cis-9,10-epoxystearate into threo-9,10-dihydroxystearate have been detected in soybean (Glycine max) seedlings. The major activity was found in the cytosol, a minor fraction being strongly associated with microsomes. The soluble enzyme, which was purified to apparent homogeneity by (NH4)2SO4 fractionation, hydrophobic, DEAE- and gel-filtration chromatographies, has a molecular mass of 64 kDa and a pI of 5.4.

scholarly journals Purification and Characterization of Asparaginase fromPhaseolus vulgarisSeeds

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Saleh A. Mohamed ◽  
Mohamed F. Elshal ◽  
Taha A. Kumosani ◽  
Alia M. Aldahlawi
Keyword(s):  
Acute Lymphoblastic Leukemia ◽  
Lymphoblastic Leukemia ◽  
Potential Candidate ◽  
Purification And Characterization ◽  
Apparent Homogeneity ◽  
Wide Range ◽  
Optimum Ph ◽  
Glutaminase Activity ◽  
Low Activity

L-asparaginase from bacteria has been used in treatment of acute lymphoblastic leukemia. The aim of this study was to purify and characterize L-asparaginase fromPhaseolus vulgarisseeds instead of microbial sources. L-asparaginase was purified to apparent homogeneity. The enzyme has molecular mass of 79 kDa. The purified asparaginase had very low activity toward a number of asparagine and glutamine analogues. L-asparaginase was free from glutaminase activity. Kinetic parameters, Km andVmax of purified enzyme, were found to be 6.72 mM and 0.16 μM, respectively. The enzyme had optimum pH at 8.0. The enzyme showed high stability at alkaline pH (pH 7.5–9.0) when incubated for up to 24 h. L-asparaginase had the same temperature optimum and thermal stability at 37°C. K+was able to greatly enhance the activity of asparaginase by 150% compared with other metals tested. In conclusion, L-asparaginase showed no glutaminase activity and good stability over a wide range of physiological conditions, and thus it could be used as a potential candidate for treatment of acute lymphoblastic leukemia.

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