101
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Friedrich J, Kern S. Hydrolysis of native proteins by keratinolytic protease of Doratomyces microsporus. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1177(02)00132-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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102
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Pinsker M, Friedrich J. Methyl group rotational tunneling splittings and spin conversion dynamics:p-chlorotoluene in cyclohexane. J Chem Phys 2002. [DOI: 10.1063/1.1504432] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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103
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Ponkratov VV, Friedrich J, Vanderkooi JM. Solvent effects on conformational dynamics of proteins: Cytochrome c in a dried trehalose film. J Chem Phys 2002. [DOI: 10.1063/1.1498459] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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104
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Zollfrank J, Friedrich J. Pressure shift and solvent shift: a hole-burning study of resorufin-doped glasses. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100199a013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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105
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Pschierer H, Friedrich J, Falk H, Schmitzberger W. Molecular interactions and correlation phenomena between pressure shift and solvent shift: a spectral hole-burning study. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100128a026] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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106
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Schellenberg P, Zollfrank J, Friedrich J. Investigation of "site-effects" in spectral diffusion broadening of optical holes in glasses. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100378a003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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107
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Gradl G, Feis A, Friedrich J. Lorentzian antihole formation through optically-induced spin conversion in doped n-octane crystals. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100184a012] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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108
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Gradl G, Friedrich J, Daltrozzo E. Spectroscopy of the triplet state of pseudoisocyanine molecular aggregates. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100369a020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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109
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Gafert J, Ober C, Orth K, Friedrich J. Thermal Broadening of an Optical Transition in a Chromoprotein between 50 mK and 15 K. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100039a051] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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110
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Friedrich J, Scheer H, Zickendraht-Wendelstadt B, Haarer D. High-resolution optical studies on C-phycocyanin via photochemical hole burning. J Am Chem Soc 2002. [DOI: 10.1021/ja00395a006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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111
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Friedrich J, Rabolt JF. Structural studies of phase transitions in poly(di-n-alkylsiloxanes). 1. Poly(dimethylsiloxane) and poly(diethylsiloxane). Macromolecules 2002. [DOI: 10.1021/ma00174a048] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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112
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Koehler W, Breinl W, Friedrich J. Laser photochemistry with polarized light in low-temperature glasses. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100258a010] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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113
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Gafert J, Friedrich J, Vanderkooi JM, Fidy J. Correlation between Protein Conformation and Prosthetic Group Configuration as Tested by pH Effects: A Hole-Burning Study on Mesoporphyrin-IX-Substituted Horseradish Peroxidase. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100059a040] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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114
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Friedrich J, Gradišar H, Mandin D, Chaumont JP. Screening fungi for synthesis of keratinolytic enzymes. Lett Appl Microbiol 2002. [DOI: 10.1046/j.1365-2672.1999.00485.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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115
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Bartsch P, Baumann D, Bermuth J, Böhm R, Bohinc K, Bosnar D, Ding M, Distler M, Drechsel D, Elsner D, Ewald I, Friedrich J, Friedrich JM, Grözinger S, Hedicke S, Jennewein P, Kahrau M, Kamalov SS, Klein F, Krygier KW, Liesenfeld A, Merkel H, Merle P, Müller U, Neuhausen R, Pospischil T, Potokar M, Rosner G, Schmieden H, Seimetz M, Süle A, Tiator L, Wagner A, Walcher T, Weis M. Measurement of the beam-helicity asymmetry in the p((-->)e,e'p)pi(0) reaction at the energy of the Delta(1232) resonance. PHYSICAL REVIEW LETTERS 2002; 88:142001. [PMID: 11955140 DOI: 10.1103/physrevlett.88.142001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2001] [Indexed: 05/23/2023]
Abstract
In a p((-->)e,e'p)pi(0) out-of-plane coincidence experiment at the three-spectrometer setup of the Mainz Microtron MAMI, the beam-helicity asymmetry has been precisely measured around the energy of the Delta(1232) resonance and Q(2) = 0.2(GeV/c)(2). The results are in disagreement with three up-to-date model calculations. This is interpreted as a lack of understanding of the nonresonant background, which in dynamical models is related to the pion cloud.
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116
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Schlichter J, Friedrich J, Herenyi L, Fidy J. Deuteration Effects on the Conformational Dynamics of Proteins in a Trehalose Glass. J Phys Chem B 2002. [DOI: 10.1021/jp012316e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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117
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Molchanov A, Hilburger U, Friedrich J, Finkbeiner M, Wehrhan G, Müller G. Experimental Verification of the Numerical Model for a CaF2 Crystal Growth Process. CRYSTAL RESEARCH AND TECHNOLOGY 2002. [DOI: 10.1002/1521-4079(200202)37:1<77::aid-crat77>3.0.co;2-k] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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118
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Merkel H, Bartsch P, Baumann D, Bermuth J, Bernstein AM, Bohinc K, Böhm R, Clawiter N, Derber S, Ding M, Distler MO, Ewald I, Friedrich JM, Friedrich J, Jennewein P, Kahrau M, Kohl M, Krygier KW, Kuss M, Liesenfeld A, Merle P, Miskimen RA, Müller U, Neuhausen R, Pavan MM, Pospischil T, Potokar M, Rosner G, Schmieden H, Seimetz M, Sirca S, Wagner A, Walcher T, Weis M. Neutral pion threshold production at Q(2) = 0.05 GeV(2)/c(2) and chiral perturbation theory. PHYSICAL REVIEW LETTERS 2002; 88:012301. [PMID: 11800938 DOI: 10.1103/physrevlett.88.012301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2001] [Indexed: 05/23/2023]
Abstract
New data are presented on the p(e,e'p)pi(0) reaction at threshold at a four-momentum transfer of Q(2) = 0.05 GeV(2)/c(2). The data were taken with the three-spectrometer setup of the A1 Collaboration at the Mainz Microtron MAMI. The complete center of mass solid angle was covered up to a center of mass energy of 4 MeV above threshold. Combined with measurements at three different values of the virtual photon polarization epsilon, the structure functions sigma(T), sigma(L), sigma(TT), and sigma(TL) are determined. The results are compared with calculations in heavy baryon chiral perturbation theory and with a phenomenological model. The measured cross section is significantly smaller than both predictions.
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119
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Steingruber SM, Friedrich J, Gächter R, Wehrli B. Measurement of denitrification in sediments with the 15N isotope pairing technique. Appl Environ Microbiol 2001; 67:3771-8. [PMID: 11525966 PMCID: PMC93090 DOI: 10.1128/aem.67.9.3771-3778.2001] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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120
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Petrunkina AM, Friedrich J, Drommer W, Bicker G, Waberski D, Töpfer-Petersen E. Kinetic characterization of the changes in protein tyrosine phosphorylation of membranes, cytosolic Ca2+ concentration and viability in boar sperm populations selected by binding to oviductal epithelial cells. Reproduction 2001; 122:469-80. [PMID: 11597312 DOI: 10.1530/rep.0.1220469] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
On reaching the oviduct, spermatozoa are retained in the isthmic region of the oviduct until ovulation occurs. The essential steps of capacitation are co-ordinated in this region. In this study, a primary cell culture system of oviductal epithelial cells was established to investigate sperm binding to oviductal epithelium and modulation of sperm function during incubation under capacitating conditions in co-culture with oviductal epithelial cells. Epithelial cells were stripped from the oviducts of sows and cultivated for 5-7 days on Lab-Tek Chamber slides on Matrigel. The preparations on chamber slides and suspensions of control spermatozoa were incubated for 3 h in Tyrode's albumin lactate pyruvate (TALP) medium. At 3, 30, 60, 90 and 180 min the free-swimming spermatozoa were collected by washing, and membrane integrity, tyrosine phosphorylation patterns and [Ca(2+)](i) of bound, unbound and control spermatozoa were assessed with fluorescent probes (propidium iodide, Cy-3 and fluo-3-AM). The cells bound to oviductal epithelial cells showed reduced cytosolic Ca(2+) concentration, reduced and almost absent tyrosine phosphorylation of membrane proteins and higher viability at the time of the first sampling. Increases in Ca(2+) concentration and cell death occurred much more slowly during incubation in cells bound to oviductal epithelial cells compared with free-swimming spermatozoa, and no changes in tyrosine phosphorylation were observed. The preferential binding of viable, low-Ca(2+) cells with suppressed tyrosine phosphorylation and slower functional modulation of boar spermatozoa attached to oviductal epithelial cells might represent a mechanism for selecting functionally competent spermatozoa and prolonging their lifespan by delaying capacitation in the oviductal reservoir.
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121
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Vignardet C, Guillaume YC, Michel L, Friedrich J, Millet J. Comparison of two hard keratinous substrates submitted to the action of a keratinase using an experimental design. Int J Pharm 2001; 224:115-22. [PMID: 11472820 DOI: 10.1016/s0378-5173(01)00749-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The influence of temperature, pH, keratinase concentration, substrate concentration and incubation time on the soluble proteins released by a new keratinase from Doratomyces microsporus was studied with a second-order experimental design. Only 15 or 18 spectrophotometric analyses were required to determine the optimal experimental conditions for this keratinase on nail and hoof. This study was carried out by measuring, according to Smith's method, the concentration of soluble proteins released by the enzyme on two substrates: nails and sheep hooves. Results give optimum conditions for the keratinase to release the soluble proteins: pH 8.2, keratinase concentration 0.14% (weight of keratinase lyophilisate/final volume) and substrate concentration 5% (weight of nail powder/final volume) for nails; temperature 38.8 degrees C, pH 9, substrate concentration 5% (weight of hoof powder/final volume) and a 5 h 55 min incubation time for hooves.
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122
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Schlichter J, Friedrich J, Parbel M, Scheer H. Influence of isotopic substitution on the conformational dynamics of frozen proteins. J Chem Phys 2001. [DOI: 10.1063/1.1369137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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123
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Schlichter J, Friedrich J. Glasses and proteins: Similarities and differences in their spectral diffusion dynamics. J Chem Phys 2001. [DOI: 10.1063/1.1367382] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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124
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Pospischil T, Bartsch P, Baumann D, Bermuth J, Böhm R, Bohinc K, Derber S, Ding M, Distler M, Drechsel D, Elsner D, Ewald I, Friedrich J, Friedrich JM, Geiges R, Hedicke S, Jennewein P, Kahrau M, Kamalov SS, Klein F, Krygier KW, Lac J, Liesenfeld A, McIntyre J, Merkel H, Merle P, Müller U, Neuhausen R, Potokar M, Ransome RD, Rohe D, Rosner G, Schmieden H, Seimetz M, Sirca S, Sick I, Süle A, Tiator L, Wagner A, Walcher T, Warren GA, Weis M. Measurement of the recoil polarization in the p(e-->, e'p-->)pi(0) reaction at the Delta(1232) resonance. PHYSICAL REVIEW LETTERS 2001; 86:2959-2962. [PMID: 11290082 DOI: 10.1103/physrevlett.86.2959] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2000] [Indexed: 05/23/2023]
Abstract
The recoil proton polarization has been measured in the p(e-->,e'p-->)pi(0) reaction in parallel kinematics around W = 1232 MeV, Q2 = 0.121 (GeV/c)2, and epsilon = 0.718 using the polarized cw electron beam of the Mainz Microtron. All three proton polarization components, Px/P(e) = (-11.4+/-1.3+/-1.4)%, P(y) = (-43.1+/-1.3+/-2.2)%, and P(z)/P(e) = (56.2+/-1.5+/-2.6)%, could be measured simultaneously. The Coulomb quadrupole to magnetic dipole ratio, CMR = (-6.4+/-0.7(stat)+/-0.8(syst))%, was determined from Px in the framework of the Mainz Unitary Isobar Model. The consistency among the reduced polarizations and the extraction of the ratio of longitudinal-to-transverse response is discussed.
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125
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Schlichter J, Friedrich J, Herenyi L, Fidy J. Trehalose effect on low temperature protein dynamics: fluctuation and relaxation phenomena. Biophys J 2001; 80:2011-7. [PMID: 11259314 PMCID: PMC1301390 DOI: 10.1016/s0006-3495(01)76171-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
We performed spectral diffusion experiments in trehalose-enriched glycerol/buffer-glass on horseradish peroxidase where the heme was replaced by metal-free mesoporphyrin IX, and compared them with the respective behavior in a pure glycerol/buffer-glass (Schlichter et al., J. Chem. Phys. 2000, 112:3045-3050). Trehalose has a significant influence: spectral diffusion broadening speeds up compared to the trehalose-free glass. This speeding up is attributed to a shortening of the correlation time of the frequency fluctuations most probably by preventing water molecules from leaving the protein interior. Superimposed to the frequency fluctuation dynamics is a relaxation dynamics that manifests itself as an aging process in the spectral diffusion broadening. Although the trehalose environment speeds up the fluctuations, it does not have any influence on the relaxation. Both relaxation and fluctuations are governed by power laws in time. The respective exponents do not seem to change with the protein environment. From the spectral dynamics, the mean square displacement in conformation space can be determined. It is governed by anomalous diffusion. The associated frequency correlation time is incredibly long, demonstrating that proteins at low temperatures are truly nonergodic systems.
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