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Simone Dell’Acqua Isabel Moura José J. G. Moura Sofia R. Pauleta 《Journal of biological inorganic chemistry》2011,16(8):1241-1254
Identifying redox partners and the interaction surfaces is crucial for fully understanding electron flow in a respiratory
chain. In this study, we focused on the interaction of nitrous oxide reductase (N2OR), which catalyzes the final step in bacterial denitrification, with its physiological electron donor, either a c-type cytochrome or a type 1 copper protein. The comparison between the interaction of N2OR from three different microorganisms, Pseudomonas nautica, Paracoccus denitrificans, and Achromobacter cycloclastes, with their physiological electron donors was performed through the analysis of the primary sequence alignment, electrostatic
surface, and molecular docking simulations, using the bimolecular complex generation with global evaluation and ranking algorithm.
The docking results were analyzed taking into account the experimental data, since the interaction is suggested to have either
a hydrophobic nature, in the case of P. nautica N2OR, or an electrostatic nature, in the case of P. denitrificans N2OR and A. cycloclastes N2OR. A set of well-conserved residues on the N2OR surface were identified as being part of the electron transfer pathway from the redox partner to N2OR (Ala495, Asp519, Val524, His566 and Leu568 numbered according to the P. nautica N2OR sequence). Moreover, we built a model for Wolinella succinogenes N2OR, an enzyme that has an additional c-type-heme-containing domain. The structures of the N2OR domain and the c-type-heme-containing domain were modeled and the full-length structure was obtained by molecular docking simulation of these
two domains. The orientation of the c-type-heme-containing domain relative to the N2OR domain is similar to that found in the other electron transfer complexes. 相似文献
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Jean-Jacques Bernardini Caroline Linget-Morice François Hoh S. Karen Collinson Pavel Kyslík William J. Page Anne Dell Mohamed A. Abdallah 《Biometals》1996,9(2):107-120
Two major azoverdins were isolated from the cultures of Azomonas macrocytogenes ATCC 12334 grown in irondeficient medium. Their structures have been established using fast atom bombardment-mass spectroscopy, homonuclear and heteronuclear two-dimensional 15N, 13C and 1H NMR, and circular dichroism techniques. These siderophores are chromopeptides possessing at the N-terminal end of their peptide chain the chromophore derived from 2,3-diamino-6,7-dihydroxyquinoline common to pyoverdins. The linear peptide chain (l)-Hse-(d)-AcOHOrn-(d)-Ser-(l)-AcOHOrn-(d)-Hse-(l)-CTHPMD has at its C-terminal end a new natural amino acid which is the result of the condensation of 1 mol of homoserine and 1 mol of 2,4-diaminobutyric acid forming a cyclic amidine belonging to the tetrahydropyrimidine family: 2-homoseryl-4-carboxyl-3,4,5,6-tetrahydropyrimidine. The azoverdins differ only by a substitutent bound to the nitrogen on C-3 of the chromophore: azoverdin, the most abundant one, possesses a succinamide moiety, whereas azoverdin A bears a succinic acid moiety. 15N-labelled azoverdin afforded readily, after the complete assignment of the 15N spectrum of the siderophore, a sequence determination of the peptidic part of the molecule and gave evidence for the presence of two tetrahydropyrimidine groups on the molecule: one on the chromophore and the second at the C-terminal end of the siderophore. 相似文献
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Wissal M’sehli Nahida Jellali Marta Dell’Orto Chedly Abdelly Graziano Zocchi Mohamed Gharsalli 《Plant Growth Regulation》2011,64(3):221-230
The aim of this research was to study the responses of two lines of Medicago ciliaris: TN11.11 and TN8.7 to iron deficiency under saline conditions. However; the paper showed also the results of a preliminary
study which report the contrastive responses of the two lines to salinity. We found that plant growth and chlorophyll content
of TN11.11 line were more affected by salinity than TN8.7. The severity of symptoms was linked to the sodium accumulation
in shoots as well as a limitation of potassium uptake. Our data allowed us to note that TN8.7 line is less sensitive and can
better cope with the salinity. Concerning the effect of salinity on iron deficiency responses, we noted that root PM H+-ATPase and FCR activities were reduced when iron deficiency was associated with salinity. This probably explained the decrease
of Fe uptake. On the contrary, PEPC activity was not affected. 相似文献
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Piyali Sabui Sadhucharan Mallick Kshitij RB Singh Arunadevi Natarajan Ranjana Verma Jay Singh Ravindra Pratap Singh 《Luminescence》2023,38(7):1047-1063
Food safety and quality are among the most significant and prevalent research areas worldwide. The fabrication of appropriate technical procedures or devices for the recognition of hazardous features in foods is essential to safeguard food materials. In the recent era, developing high-performance sensors based on carbon nanomaterial for food safety investigation has made noteworthy progress. Hence this review briefly highlights the different detection approaches (colorimetric sensor, fluorescence sensor, surface-enhanced Raman scattering, surface plasmon resonance, chemiluminescence, and electroluminescence), functional carbon nanomaterials with various dimensions (quantum dots, graphene quantum dots) and detection mechanisms. Further, this review emphasizes the assimilation of carbon nanomaterials with optical sensors to identify multiple contaminants in food products. The insights of carbon-based nanomaterials optical sensors for pesticides and insecticides, toxic metals, antibiotics, microorganisms, and mycotoxins detection are described in detail. Finally, the opportunities and future perspectives of nanomaterials-based optical analytical approaches for detecting various food contaminants are discussed. 相似文献