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  1. Article ; Online: HDX-MS performed on BtuB in

    Zmyslowski, Adam M / Baxa, Michael C / Gagnon, Isabelle A / Sosnick, Tobin R

    Proceedings of the National Academy of Sciences of the United States of America

    2022  Volume 119, Issue 20, Page(s) e2119436119

    Abstract: To import large metabolites across the outer membrane of gram-negative bacteria, TonB-dependent transporters (TBDTs) undergo significant conformational change. After substrate binding in BtuB, the Escherichia coli vitamin B12 TBDT, TonB binds and couples ...

    Abstract To import large metabolites across the outer membrane of gram-negative bacteria, TonB-dependent transporters (TBDTs) undergo significant conformational change. After substrate binding in BtuB, the Escherichia coli vitamin B12 TBDT, TonB binds and couples BtuB to the inner-membrane proton motive force that powers transport [N. Noinaj, M. Guillier, T. J. Barnard, S. K. Buchanan, Annu. Rev. Microbiol. 64, 43–60 (2010)]. However, the role of TonB in rearranging the plug domain of BtuB to form a putative pore remains enigmatic. Some studies focus on force-mediated unfolding [S. J. Hickman, R. E. M. Cooper, L. Bellucci, E. Paci, D. J. Brockwell, Nat. Commun. 8, 14804 (2017)], while others propose force-independent pore formation by TonB binding [T. D. Nilaweera, D. A. Nyenhuis, D. S. Cafiso, eLife 10, e68548 (2021)], leading to breakage of a salt bridge termed the “Ionic Lock.” Our hydrogen–deuterium exchange/mass spectrometry (HDX-MS) measurements in E. coli outer membranes find that the region surrounding the Ionic Lock, far from the B12 site, is fully destabilized upon substrate binding. A comparison of the exchange between the B12-bound and the B12+TonB–bound complexes indicates that B12 binding is sufficient to unfold the Ionic Lock region, with the subsequent binding of a TonB fragment having much weaker effects. TonB binding accelerates exchange in the third substrate-binding loop, but pore formation does not obviously occur in this or any region. This study provides a detailed structural and energetic description of the early stages of B12 passage that provides support both for and against current models of the transport process.
    MeSH term(s) Allosteric Regulation ; Bacterial Outer Membrane Proteins/chemistry ; Bacterial Outer Membrane Proteins/metabolism ; Biological Transport ; Escherichia coli/metabolism ; Escherichia coli Proteins/chemistry ; Escherichia coli Proteins/metabolism ; Hydrogen Deuterium Exchange-Mass Spectrometry ; Membrane Proteins/chemistry ; Membrane Proteins/metabolism ; Membrane Transport Proteins/chemistry ; Membrane Transport Proteins/metabolism ; Protein Binding ; Protein Domains ; Protein Folding ; Vitamin B 12/metabolism
    Chemical Substances Bacterial Outer Membrane Proteins ; BtuB protein, E coli ; Escherichia coli Proteins ; Membrane Proteins ; Membrane Transport Proteins ; tonB protein, E coli ; Vitamin B 12 (P6YC3EG204)
    Language English
    Publishing date 2022-05-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2119436119
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Oxysterols as a biomarker in diseases.

    Zmysłowski, Adam / Szterk, Arkadiusz

    Clinica chimica acta; international journal of clinical chemistry

    2019  Volume 491, Page(s) 103–113

    Abstract: Cholesterol is one of the most important chemical substances as a structural element in human cells, and it is very susceptible to oxidation reactions that form oxysterol. Oxysterols exhibit almost the exact structure as cholesterol and a cholesterol ... ...

    Abstract Cholesterol is one of the most important chemical substances as a structural element in human cells, and it is very susceptible to oxidation reactions that form oxysterol. Oxysterols exhibit almost the exact structure as cholesterol and a cholesterol precursor (7-dehydrocholesterol) with an additional hydroxyl, epoxy or ketone moiety. The oxidation reaction is performed via an enzymatic or non-enzymatic mechanism. The wide array of enzymatic oxysterols encountered in the human body varies in origin and function. Oxysterols establish a concentration equilibrium in human body fluids. Disease may alter the equilibrium, and oxysterols may be used as a diagnostic tool. The current review presents the possibility of using non-enzymatic oxysterols and disturbances in enzymatic oxysterol equilibrium in the human body as a potential biomarker for diagnosing and/or monitoring of the progression of various diseases.
    MeSH term(s) Animals ; Biomarkers/metabolism ; Disease ; Humans ; Oxysterols/metabolism
    Chemical Substances Biomarkers ; Oxysterols
    Language English
    Publishing date 2019-01-24
    Publishing country Netherlands
    Document type Journal Article ; Review
    ZDB-ID 80228-1
    ISSN 1873-3492 ; 0009-8981
    ISSN (online) 1873-3492
    ISSN 0009-8981
    DOI 10.1016/j.cca.2019.01.022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Separation of menaquinone-7 geometric isomers by semipreparative high-performance liquid chromatography with silver complexation and identification by nuclear magnetic resonance

    Bus, Katarzyna / Sitkowski, Jerzy / Bocian, Wojciech / Zmysłowski, Adam / Ofiara, Karol / Szterk, Arkadiusz

    Food chemistry. 2022 Jan. 30, v. 368

    2022  

    Abstract: Dietary supplements containing vitamin K2 are often used to prevent osteoporosis, vascular calcification and coronary heart disease. It has been shown that some of these products contain a mixture of menaquinone-7 geometric isomers. Since the geometric ... ...

    Abstract Dietary supplements containing vitamin K2 are often used to prevent osteoporosis, vascular calcification and coronary heart disease. It has been shown that some of these products contain a mixture of menaquinone-7 geometric isomers. Since the geometric shape may influence biological activity, there was a need for a semipreparative method to isolate single compounds for further studies. Here, we present an argentation chromatographic method for the separation of menaquinone-7 isomers and an nuclear magnetic resonance (NMR) methodology for the configuration assignment of isoprenoid side chain. The DFT calculations were performed to determine more energetically favorable complexes between the cis or trans menaquinone-7 isomers and the silver cation. Seventeen components were resolved, and fractions were collected and subjected to NMR study. Structures and chemical shifts for thirteen new compounds were assigned, and the identity of three known compounds was confirmed.
    Keywords bioactive properties ; calcification ; cations ; coronary disease ; food chemistry ; geometry ; high performance liquid chromatography ; isoprenoids ; menaquinones ; nuclear magnetic resonance spectroscopy ; osteoporosis ; silver
    Language English
    Dates of publication 2022-0130
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2021.130890
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  4. Article ; Online: N

    Zmysłowski, Adam / Książek, Iza / Szterk, Arkadiusz

    Molecules (Basel, Switzerland)

    2020  Volume 25, Issue 22

    Abstract: A GC-MS/MS method with EI ionization was developed and validated to detect and ... ...

    Abstract A GC-MS/MS method with EI ionization was developed and validated to detect and quantify
    MeSH term(s) Artifacts ; Calibration ; Dimethylnitrosamine/chemistry ; Drug Contamination ; Drug Design ; Europe ; Gas Chromatography-Mass Spectrometry ; Limit of Detection ; Linear Models ; Metformin/analysis ; Metformin/chemistry ; Pharmaceutical Preparations/analysis ; Powders ; Solvents ; Tablets ; Tandem Mass Spectrometry ; Temperature
    Chemical Substances Pharmaceutical Preparations ; Powders ; Solvents ; Tablets ; Metformin (9100L32L2N) ; Dimethylnitrosamine (M43H21IO8R)
    Language English
    Publishing date 2020-11-13
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 1413402-0
    ISSN 1420-3049 ; 1431-5165 ; 1420-3049
    ISSN (online) 1420-3049
    ISSN 1431-5165 ; 1420-3049
    DOI 10.3390/molecules25225304
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Synthesis of Oxidized 3β,3'β-Disteryl Ethers and Search after High-Temperature Treatment of Sterol-Rich Samples.

    Zmysłowski, Adam / Sitkowski, Jerzy / Bus, Katarzyna / Michalska, Katarzyna / Szterk, Arkadiusz

    International journal of molecular sciences

    2021  Volume 22, Issue 19

    Abstract: It was proven that sterols subjected to high-temperature treatment can be concatenated, which results in polymeric structures, e.g., 3β,3'β-disteryl ethers. However, it was also proven that due to increased temperature in oxygen-containing conditions, ... ...

    Abstract It was proven that sterols subjected to high-temperature treatment can be concatenated, which results in polymeric structures, e.g., 3β,3'β-disteryl ethers. However, it was also proven that due to increased temperature in oxygen-containing conditions, sterols can undergo various oxidation reactions. This study aimed to prove the existence and perform quantitative analysis of oxidized 3β,3'β-disteryl ethers, which could form during high-temperature treatment of sterol-rich samples. Samples were heated at 180, 200 and 220 °C for 0.5 to 4 h. Quantitative analyses of the oxidized 3β,3'β-disteryl ethers were performed with liquid extraction, solid-phase extraction and liquid chromatography coupled with mass spectrometry. Additionally, to perform this analysis, the appropriate standards of all oxidized 3β,3'β-disteryl ethers were prepared. Eighteen various oxidized 3β,3'β-disteryl ethers (derivatives of 3β,3'β-dicholesteryl ether, 3β,3'β-disitosteryl ether and 3β,3'β-distigmasteryl ether) were prepared. Additionally, the influence of metal compounds on the mechanism of ether formation at high temperatures was investigated.
    MeSH term(s) Ethers/chemical synthesis ; Ethers/chemistry ; Mass Spectrometry ; Oxidation-Reduction ; Solid Phase Extraction ; Sterols/chemistry
    Chemical Substances Ethers ; Sterols
    Language English
    Publishing date 2021-09-27
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2019364-6
    ISSN 1422-0067 ; 1422-0067 ; 1661-6596
    ISSN (online) 1422-0067
    ISSN 1422-0067 ; 1661-6596
    DOI 10.3390/ijms221910421
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Development of in vivo HDX-MS with applications to a TonB-dependent transporter and other proteins.

    Lin, Xiaoxuan / Zmyslowski, Adam M / Gagnon, Isabelle A / Nakamoto, Robert K / Sosnick, Tobin R

    Protein science : a publication of the Protein Society

    2022  Volume 31, Issue 9, Page(s) e4402

    Abstract: Hydrogen-deuterium exchange mass spectrometry (HDX-MS) is a powerful tool that monitors protein dynamics in solution. However, the reversible nature of HDX labels has largely limited the application to in vitro systems. Here, we describe a protocol for ... ...

    Abstract Hydrogen-deuterium exchange mass spectrometry (HDX-MS) is a powerful tool that monitors protein dynamics in solution. However, the reversible nature of HDX labels has largely limited the application to in vitro systems. Here, we describe a protocol for measuring HDX-MS in living Escherichia coli cells applied to BtuB, a TonB-dependent transporter found in outer membranes (OMs). BtuB is a convenient and biologically interesting system for testing in vivo HDX-MS due to its controllable HDX behavior and large structural rearrangements that occur during the B12 transport cycle. Our previous HDX-MS study in native OMs provided evidence for B12 binding and breaking of a salt bridge termed the Ionic Lock, an event that leads to the unfolding of the amino terminus. Although purified OMs provide a more native-like environment than reconstituted systems, disruption of the cell envelope during lysis perturbs the linkage between BtuB and the TonB complex that drives B12 transport. The in vivo HDX response of BtuB's plug domain (BtuBp) to B12 binding corroborates our previous in vitro findings that B12 alone is sufficient to break the Ionic Lock. In addition, we still find no evidence of B12 binding-induced unfolding in other regions of BtuBp that could enable B12 passage. Our protocol was successful in reporting on the HDX of several endogenous E. coli proteins measured in the same measurement. Our success in performing HDX in live cells opens the possibility for future HDX-MS studies in a native cellular environment. IMPORTANCE: We present a protocol for performing in vivo HDX-MS, focusing on BtuB, a protein whose native membrane environment is believed to be mechanistically important for B12 transport. The in vivo HDX-MS data corroborate the conclusions from our previous in vitro HDX-MS study of the allostery initiated by B12 binding. Our success with BtuB and other proteins opens the possibility for performing additional HDX-MS studies in a native cellular environment.
    MeSH term(s) Bacterial Outer Membrane Proteins/chemistry ; Deuterium Exchange Measurement ; Escherichia coli/genetics ; Escherichia coli/metabolism ; Escherichia coli Proteins/chemistry ; Hydrogen Deuterium Exchange-Mass Spectrometry ; Membrane Transport Proteins/chemistry ; Vitamin B 12/metabolism
    Chemical Substances Bacterial Outer Membrane Proteins ; Escherichia coli Proteins ; Membrane Transport Proteins ; Vitamin B 12 (P6YC3EG204)
    Language English
    Publishing date 2022-08-30
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1106283-6
    ISSN 1469-896X ; 0961-8368
    ISSN (online) 1469-896X
    ISSN 0961-8368
    DOI 10.1002/pro.4402
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  7. Article ; Online: Current knowledge on the mechanism of atherosclerosis and pro-atherosclerotic properties of oxysterols.

    Zmysłowski, Adam / Szterk, Arkadiusz

    Lipids in health and disease

    2017  Volume 16, Issue 1, Page(s) 188

    Abstract: Due to the fact that one of the main causes of worldwide deaths are directly related to atherosclerosis, scientists are constantly looking for atherosclerotic factors, in an attempt to reduce prevalence of this disease. The most important known pro- ... ...

    Abstract Due to the fact that one of the main causes of worldwide deaths are directly related to atherosclerosis, scientists are constantly looking for atherosclerotic factors, in an attempt to reduce prevalence of this disease. The most important known pro-atherosclerotic factors include: elevated levels of LDL, low HDL levels, obesity and overweight, diabetes, family history of coronary heart disease and cigarette smoking. Since finding oxidized forms of cholesterol - oxysterols - in lesion in the arteries, it has also been presumed they possess pro-atherosclerotic properties. The formation of oxysterols in the atherosclerosis lesions, as a result of LDL oxidation due to the inflammatory response of cells to mechanical stress, is confirmed. However, it is still unknown, what exactly oxysterols cause in connection with atherosclerosis, after gaining entry to the human body e.g., with food containing high amounts of cholesterol, after being heated. The in vivo studies should provide data to finally prove or disprove the thesis regarding the pro-atherosclerotic prosperities of oxysterols, yet despite dozens of available in vivo research some studies confirm such properties, other disprove them. In this article we present the current knowledge about the mechanism of formation of atherosclerotic lesions and we summarize available data on in vivo studies, which investigated whether oxysterols have properties to cause the formation and accelerate the progress of the disease. Additionally we will try to discuss why such different results were obtained in all in vivo studies.
    Language English
    Publishing date 2017-10-02
    Publishing country England
    Document type Journal Article ; Review
    ISSN 1476-511X
    ISSN (online) 1476-511X
    DOI 10.1186/s12944-017-0579-2
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  8. Article ; Online: Synthesis and search for 3β,3'β-disteryl ethers after high-temperature treatment of sterol-rich samples.

    Zmysłowski, Adam / Sitkowski, Jerzy / Bus, Katarzyna / Ofiara, Karol / Szterk, Arkadiusz

    Food chemistry

    2020  Volume 329, Page(s) 127132

    Abstract: It has been proven that at increased temperature, sterols can undergo various chemical reactions e.g., oxidation, dehydrogenation, dehydration and polymerisation. The objectives of this study are to prove the existence of dimers and to quantitatively ... ...

    Abstract It has been proven that at increased temperature, sterols can undergo various chemical reactions e.g., oxidation, dehydrogenation, dehydration and polymerisation. The objectives of this study are to prove the existence of dimers and to quantitatively analyse the dimers (3β,3'β-disteryl ethers). Sterol-rich samples were heated at 180 °C, 200 °C and 220 °C for 1 to 5 h. Quantitative analyses of the 3β,3'β-disteryl ethers were conducted using liquid extraction, solid-phase extraction and gas chromatography coupled with mass spectrometry. Additionally, for the analyses, suitable standards were synthetized from native sterols. To identify the mechanism of 3β,3'β-disteryl ether formation at high temperatures, an attempt was made to use the proposed synthesis method. Additionally, due to the association of sterols and sterol derivatives with atherosclerosis, preliminary studies with synthetized 3β,3'β-disteryl ethers on endothelial cells were conducted.
    MeSH term(s) Cell Line ; Endothelial Cells ; Ethers/chemical synthesis ; Ethers/chemistry ; Gas Chromatography-Mass Spectrometry ; Humans ; Mass Spectrometry ; Oxidation-Reduction ; Solid Phase Extraction ; Sterols/chemistry ; Temperature
    Chemical Substances Ethers ; Sterols
    Language English
    Publishing date 2020-05-23
    Publishing country England
    Document type Journal Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2020.127132
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Separation of menaquinone-7 geometric isomers by semipreparative high-performance liquid chromatography with silver complexation and identification by nuclear magnetic resonance.

    Bus, Katarzyna / Sitkowski, Jerzy / Bocian, Wojciech / Zmysłowski, Adam / Ofiara, Karol / Szterk, Arkadiusz

    Food chemistry

    2021  Volume 368, Page(s) 130890

    Abstract: Dietary supplements containing vitamin K2 are often used to prevent osteoporosis, vascular calcification and coronary heart disease. It has been shown that some of these products contain a mixture of menaquinone-7 geometric isomers. Since the geometric ... ...

    Abstract Dietary supplements containing vitamin K2 are often used to prevent osteoporosis, vascular calcification and coronary heart disease. It has been shown that some of these products contain a mixture of menaquinone-7 geometric isomers. Since the geometric shape may influence biological activity, there was a need for a semipreparative method to isolate single compounds for further studies. Here, we present an argentation chromatographic method for the separation of menaquinone-7 isomers and an nuclear magnetic resonance (NMR) methodology for the configuration assignment of isoprenoid side chain. The DFT calculations were performed to determine more energetically favorable complexes between the cis or trans menaquinone-7 isomers and the silver cation. Seventeen components were resolved, and fractions were collected and subjected to NMR study. Structures and chemical shifts for thirteen new compounds were assigned, and the identity of three known compounds was confirmed.
    MeSH term(s) Chromatography, High Pressure Liquid ; Magnetic Resonance Spectroscopy ; Silver ; Vitamin K 2/analogs & derivatives
    Chemical Substances Vitamin K 2 (11032-49-8) ; Silver (3M4G523W1G) ; menaquinone 7 (8427BML8NY)
    Language English
    Publishing date 2021-08-18
    Publishing country England
    Document type Journal Article
    ZDB-ID 243123-3
    ISSN 1873-7072 ; 0308-8146
    ISSN (online) 1873-7072
    ISSN 0308-8146
    DOI 10.1016/j.foodchem.2021.130890
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Application of hydrophilic interaction liquid chromatography for the quantification of succinylcholine in Active Pharmaceutical Ingredient and medicinal product. Identification of new impurities of succinylcholine chloride

    Szterk, Arkadiusz / Zmysłowski, Adam / Gorinstein, Shela

    Heliyon. 2018 Dec., v. 4, no. 12

    2018  

    Abstract: A new method, using hydrophilic interaction chromatography (HILIC), for quantification of succinylcholine and impurities in Active Pharmaceutical Ingredient (API), as well as in the medicinal product, was developed. Additionally, the new impurities in ... ...

    Abstract A new method, using hydrophilic interaction chromatography (HILIC), for quantification of succinylcholine and impurities in Active Pharmaceutical Ingredient (API), as well as in the medicinal product, was developed. Additionally, the new impurities in API were discovered using ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF) technique. The substances were quantified with the application of a UV detector (λ = 214 nm). Chromatographic separation was performed isocratically with the application of 30% phosphate buffer (pH 4,0; 0.05 M) in ACN as a mobile phase. A major feature of the developed method is a very high resolution (Rs > 3), between succinylcholine and its main impurity - succinylmonocholine, whereas the width of peak bands does not exceed 0.7 min. A low value of limits of detection (LOD) were obtained for succinic acid, succinylmonocholine and for succinylcholine, which amounted to 2.4, 6.0 and 11.5 μg ml⁻¹, respectively. Another feature of the developed method is linearity in a very wide range of concentrations: 7.3 μg ml⁻¹ – 670 μg ml⁻¹ amounting to R² = 0.999. The recovery provided by this method at three different fortification levels for all analytes remained within the following range: 95.7 – 98.9 %. Intra-day and inter-day precision remained within the following range: 1.0 – 5.9 % coefficient of variation (CV), whereas accuracy within the range: −1.3 – 6.3. The developed method of hydrophilic interactions made it possible to quantify two new impurities, probably originating from the synthesis of an API: [2-(trimethylaminium)ethyl]-[2ʹ-(trimethylaminium)vinyl] succinate and [2-(dimethylamino)etyl]-[2ʹ-(trimethylaminium)etyl] succinate, which were identified and described for the first time. In addition, a physicochemical form of peak doublet described in the USP as impurities was studied and it was demonstrated that these peaks are the result of the specific physicochemical interactions in ion pair chromatography.
    Keywords active pharmaceutical ingredients ; chemical species ; chlorides ; hydrophilic interaction chromatography ; hydrophilicity ; ion pair chromatography ; mass spectrometry ; pH ; phosphates ; succinic acid ; suxamethonium
    Language English
    Dates of publication 2018-12
    Publishing place Elsevier Ltd
    Document type Article
    Note NAL-AP-2-clean
    ZDB-ID 2835763-2
    ISSN 2405-8440
    ISSN 2405-8440
    DOI 10.1016/j.heliyon.2018.e01097
    Database NAL-Catalogue (AGRICOLA)

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