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  1. Article ; Online: Protein yoga: Conformational versatility of the Hemolysin II C-terminal domain detailed by NMR structures for multiple states.

    Kaplan, Anne R / Olson, Rich / Alexandrescu, Andrei T

    Protein science : a publication of the Protein Society

    2021  Volume 30, Issue 5, Page(s) 990–1005

    Abstract: The C-terminal domain of Bacillus cereus hemolysin II (HlyIIC), stabilizes the trans-membrane-pore ... P405, and structurally adjacent loops. Thermodynamic linkage analysis shows that at 25 C the cis ...

    Abstract The C-terminal domain of Bacillus cereus hemolysin II (HlyIIC), stabilizes the trans-membrane-pore formed by the HlyII toxin and may aid in target cell recognition. Initial efforts to determine the NMR structure of HlyIIC were hampered by cis/trans isomerization about the single proline at position 405 that leads to doubling of NMR resonances. We used the mutant P405M-HlyIIC that eliminates the cis proline to determine the NMR structure of the domain, which revealed a novel fold. Here, we extend earlier studies to the NMR structure determination of the cis and trans states of WT-HlyIIC that exist simultaneously in solution. The primary structural differences between the cis and trans states are in the loop that contains P405, and structurally adjacent loops. Thermodynamic linkage analysis shows that at 25 C the cis proline, which already has a large fraction of 20% in the unfolded protein, increases to 50% in the folded state due to coupling with the global stability of the domain. The P405M or P405A substitutions eliminate heterogeneity due to proline isomerization but lead to the formation of a new dimeric species. The NMR structure of the dimer shows that it is formed through domain-swapping of strand β5, the last segment of secondary structure following P405. The presence of P405 in WT-HlyIIC strongly disfavors the dimer compared to the P405M-HlyIIC or P405A-HlyIIC mutants. The WT proline may thus act as a "gatekeeper," warding off aggregative misfolding.
    MeSH term(s) Amino Acid Substitution ; Bacillus cereus/chemistry ; Bacillus cereus/genetics ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Hemolysin Proteins/chemistry ; Hemolysin Proteins/genetics ; Mutation, Missense ; Nuclear Magnetic Resonance, Biomolecular ; Protein Domains
    Chemical Substances ApxII toxin, bacteria ; Bacterial Proteins ; Hemolysin Proteins
    Language English
    Publishing date 2021-03-30
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 1106283-6
    ISSN 1469-896X ; 0961-8368
    ISSN (online) 1469-896X
    ISSN 0961-8368
    DOI 10.1002/pro.4066
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: NMR structure of the Bacillus cereus hemolysin II C-terminal domain reveals a novel fold.

    Kaplan, Anne R / Kaus, Katherine / De, Swastik / Olson, Rich / Alexandrescu, Andrei T

    Scientific reports

    2017  Volume 7, Issue 1, Page(s) 3277

    Abstract: ... toxin has a unique 94 amino acid C-terminal domain (HlyIIC). HlyIIC exhibits splitting of NMR resonances ... due to cis/trans isomerization of a single proline near the C-terminus. To overcome heterogeneity ...

    Abstract In addition to multiple virulence factors, Bacillus cereus a pathogen that causes food poisoning and life-threatening wound infections, secretes the pore-forming toxin hemolysin II (HlyII). The HlyII toxin has a unique 94 amino acid C-terminal domain (HlyIIC). HlyIIC exhibits splitting of NMR resonances due to cis/trans isomerization of a single proline near the C-terminus. To overcome heterogeneity, we solved the structure of P405M-HlyIIC, a mutant that exclusively stabilizes the trans state. The NMR structure of HlyIIC reveals a novel fold, consisting of two subdomains αA-β1-β2 and β3-β4-αB-β5, that come together in a barrel-like structure. The barrel core is fastened by three layers of hydrophobic residues. The barrel end opposite the HlyIIC-core has a positively charged surface, that by binding negatively charged moieties on cellular membranes, may play a role in target-cell surface recognition or stabilization of the heptameric pore complex. In the WT domain, dynamic flexibility occurs at the N-terminus and the first α-helix that connects the HlyIIC domain to the HlyII-core structure. In the destabilizing P405M mutant, increased flexibility is evident throughout the first subdomain, suggesting that the HlyIIC structure may have arisen through gene fusion.
    MeSH term(s) Bacillus cereus/genetics ; Bacillus cereus/metabolism ; Bacterial Proteins/chemistry ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Hemolysin Proteins/chemistry ; Hemolysin Proteins/genetics ; Hemolysin Proteins/metabolism ; Hydrogen/chemistry ; Hydrophobic and Hydrophilic Interactions ; Isomerism ; Models, Molecular ; Mutation ; Nuclear Magnetic Resonance, Biomolecular ; Protein Conformation ; Protein Folding ; Protein Interaction Domains and Motifs ; Static Electricity
    Chemical Substances Bacterial Proteins ; Hemolysin Proteins ; Hydrogen (7YNJ3PO35Z)
    Language English
    Publishing date 2017-06-12
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2615211-3
    ISSN 2045-2322 ; 2045-2322
    ISSN (online) 2045-2322
    ISSN 2045-2322
    DOI 10.1038/s41598-017-02917-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Increased rate of spontaneous clearance of hepatitis C virus in patients infected with HIV.

    Dumitru, Irina Magdalena / Rugina, Sorin / Alexandrescu, Luana / Dumitru, Eugen

    Journal of gastrointestinal and liver diseases : JGLD

    2014  Volume 23, Issue 4, Page(s) 461–462

    MeSH term(s) Coinfection ; HIV Infections/complications ; Hepacivirus/pathogenicity ; Hepatitis C/complications ; Humans ; Male
    Language English
    Publishing date 2014-12
    Publishing country Romania
    Document type Comment ; Letter
    ZDB-ID 2427021-0
    ISSN 1842-1121 ; 1841-8724
    ISSN (online) 1842-1121
    ISSN 1841-8724
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book: Modern C++ design

    Alexandrescu, Andrei

    generic programming and design patterns applied

    (The C++ in-depth series)

    2009  

    Author's details Andrei Alexandrescu
    Series title The C++ in-depth series
    Language English
    Size XXII, 323 S., graph. Darst.
    Edition 17. print.
    Publisher Addison-Wesley
    Publishing place Boston, Mass. u.a.
    Document type Book
    Note Literaturverz. S. 311 - 312
    ISBN 0201704315 ; 9780201704310
    Database Former special subject collection: coastal and deep sea fishing

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  5. Article ; Online: Pseudoscleroderma possibly induced by intravesical instillation of mitomycin C.

    Calistru, Ana Maria / Baudrier, Teresa / Mota, Alberto / Alexandrescu, Doru / Cunha, Ana Luiza / Silva, João / Azevedo, Filomena

    Journal of the American Academy of Dermatology

    2010  Volume 63, Issue 6, Page(s) e116–8

    MeSH term(s) Administration, Intravesical ; Aged ; Antibiotics, Antineoplastic/adverse effects ; Drug Eruptions/pathology ; Humans ; Male ; Mitomycin/adverse effects ; Scleroderma, Localized/chemically induced ; Scleroderma, Localized/pathology ; Urinary Bladder Neoplasms/drug therapy
    Chemical Substances Antibiotics, Antineoplastic ; Mitomycin (50SG953SK6)
    Language English
    Publishing date 2010-12
    Publishing country United States
    Document type Case Reports ; Letter
    ZDB-ID 603641-7
    ISSN 1097-6787 ; 0190-9622
    ISSN (online) 1097-6787
    ISSN 0190-9622
    DOI 10.1016/j.jaad.2010.02.036
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: NMR assignments for the cis and trans forms of the hemolysin II C-terminal domain.

    Kaplan, Anne R / Maciejewski, Mark W / Olson, Rich / Alexandrescu, Andrei T

    Biomolecular NMR assignments

    2014  Volume 8, Issue 2, Page(s) 419–423

    Abstract: ... proteins, carbohydrates, and lipids. Here we report NMR assignments for the 94-residue 10 kDa C-terminal ...

    Abstract Pathogenic bacteria secrete pore-forming toxins (PFTs) to selectively defend against immune cells and to break through cellular barriers in the host. Understanding how PFTs attack cell membranes is not only essential for therapeutic intervention but for designing agents to deliver drugs to specific human cell subtypes, for example in anti-cancer or anti-viral therapies. Many toxins contain accessory domains that help recognize specific molecular epitopes on the membranes of target cells, including proteins, carbohydrates, and lipids. Here we report NMR assignments for the 94-residue 10 kDa C-terminal accessory domain of Bacillus cereus hemolysin II, HlyIIC, that has no known structural or functional homologues. The HlyIIC domain exists in a dynamic equilibrium due to cis/trans isomerization of its Gly86-Pro87 peptide bond. The cis and trans forms are about equally populated and are in slow exchange on the NMR timescale, giving rise to separate signals for approximately half of the residues in the domain. Assignments for the cis and trans forms were achieved with the aid of a P87M mutant that stabilizes the trans form, and separate sequential walks for the two forms in 3D NMR spectra of the wild-type HlyIIC. Based on backbone chemical shifts, the domain has a α1-α2-β1-β2-β3-β4-α3-β5 order of secondary structure elements. The last strand in the trans form and in the P87M mutant is shortened near Pro87 compared to the cis form. Both cis/trans isomerization and the P87M mutation cause large chemical shift changes throughout HlyIIC, suggesting that the proline is important in stabilizing the structure of the domain. The NMR assignments pave the way for solving the structures of the multiple conformational forms of HlyIIC and establishing their mechanism of interconversion.
    MeSH term(s) Amino Acid Sequence ; Bacillus cereus ; Bacterial Proteins/chemistry ; Hemolysin Proteins/chemistry ; Molecular Sequence Data ; Nuclear Magnetic Resonance, Biomolecular ; Protein Structure, Tertiary ; Stereoisomerism
    Chemical Substances Bacterial Proteins ; Hemolysin Proteins
    Language English
    Publishing date 2014-10
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2388861-1
    ISSN 1874-270X ; 1874-2718
    ISSN (online) 1874-270X
    ISSN 1874-2718
    DOI 10.1007/s12104-013-9530-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Book: C++ coding standards

    Sutter, Herb / Alexandrescu, Andrei

    101 rules, guidelines, and best practices

    (The C++ in-depth series)

    2008  

    Title variant C-plus-plus hundred-and-one ; C-plus-plus-in-depth
    Author's details Herb Sutter; Andrei Alexandrescu
    Series title The C++ in-depth series
    Language English
    Size XV, 220 S
    Edition 7. printing
    Publisher Addison-Wesley
    Publishing place Boston, Mass
    Document type Book
    Note Literaturverz. S. 187 - 193. - Literaturangaben
    ISBN 0321113586 ; 9780321113580
    Database Former special subject collection: coastal and deep sea fishing

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  8. Article ; Online: NMR structure of the Bacillus cereus hemolysin II C-terminal domain reveals a novel fold

    Anne R. Kaplan / Katherine Kaus / Swastik De / Rich Olson / Andrei T. Alexandrescu

    Scientific Reports, Vol 7, Iss 1, Pp 1-

    2017  Volume 13

    Abstract: ... The HlyII toxin has a unique 94 amino acid C-terminal domain (HlyIIC). HlyIIC exhibits splitting of NMR ... resonances due to cis/trans isomerization of a single proline near the C-terminus. To overcome heterogeneity ...

    Abstract Abstract In addition to multiple virulence factors, Bacillus cereus a pathogen that causes food poisoning and life-threatening wound infections, secretes the pore-forming toxin hemolysin II (HlyII). The HlyII toxin has a unique 94 amino acid C-terminal domain (HlyIIC). HlyIIC exhibits splitting of NMR resonances due to cis/trans isomerization of a single proline near the C-terminus. To overcome heterogeneity, we solved the structure of P405M-HlyIIC, a mutant that exclusively stabilizes the trans state. The NMR structure of HlyIIC reveals a novel fold, consisting of two subdomains αA-β1-β2 and β3-β4-αB-β5, that come together in a barrel-like structure. The barrel core is fastened by three layers of hydrophobic residues. The barrel end opposite the HlyIIC-core has a positively charged surface, that by binding negatively charged moieties on cellular membranes, may play a role in target-cell surface recognition or stabilization of the heptameric pore complex. In the WT domain, dynamic flexibility occurs at the N-terminus and the first α-helix that connects the HlyIIC domain to the HlyII-core structure. In the destabilizing P405M mutant, increased flexibility is evident throughout the first subdomain, suggesting that the HlyIIC structure may have arisen through gene fusion.
    Keywords Medicine ; R ; Science ; Q
    Subject code 572
    Language English
    Publishing date 2017-06-01T00:00:00Z
    Publisher Nature Portfolio
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Book: C++ coding standards

    Sutter, Herb / Alexandrescu, Andrei

    101 rules, guidelines, and best practices

    (The C++ in-depth series)

    2007  

    Title variant C-plus-plus coding standards ; C-plus-plus hundred-and-one ; C-plus-plus-in-depth
    Author's details Herb Sutter; Andrei Alexandrescu
    Series title The C++ in-depth series
    Language English
    Size XV, 220 S
    Edition 4. printing
    Publisher Addison-Wesley
    Publishing place Boston
    Document type Book
    Note Literaturverz. S. 187 - 193. - Literaturangaben
    ISBN 0321113586 ; 9780321113580
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  10. Article: ZOSTER TRIGGERS IN GRAVES OPHTHALMOPATHY.

    Radulescu, V / Dumitrascu, A / Alexandrescu, D / Badiu, C

    Acta endocrinologica (Bucharest, Romania : 2005)

    2023  Volume 19, Issue 2, Page(s) 267–268

    Language English
    Publishing date 2023-10-27
    Publishing country Romania
    Document type Case Reports
    ZDB-ID 1433812-9
    ISSN 1843-066X ; 1841-0987
    ISSN (online) 1843-066X
    ISSN 1841-0987
    DOI 10.4183/aeb.2023.267
    Database MEDical Literature Analysis and Retrieval System OnLINE

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