| 1. |
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Steinbacher, S, et al.
(författare)
-
Crystal structure of phage P22 tailspike protein complexed with Salmonella sp. O-antigen receptors
- 1996
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 93:20, s. 10584-10588
-
Tidskriftsartikel (refereegranskat)abstract
- The O-antigenic repeating units of lipopolysaccharides from Salmonella serogroups A, B, and D1 serve as receptors for the phage P22 tailspike protein, which also has receptor destroying endoglycosidase (endorhamnosidase) activity, integrating the functions of both hemagglutinin and neuraminidase in influenza virus. Crystal structures of the tailspike protein in complex with oligosaccharides, comprising two O-antigenic repeating units from Salmonella typhimurium, Salmonella enteritidis, and Salmonella typhi 253Ty were determined at 1.8 A resolution. The active-site topology with Asp-392, Asp-395, and Glu-359 as catalytic residues was identified. Kinetics of binding and cleavage suggest a role of the receptor destroying endorhamnosidase activity primarily for detachment of newly assembled phages.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Broeker, N. K., et al.
(författare)
-
Single amino acid exchange in bacteriophage HK620 tailspike protein results in thousand-fold increase of its oligosaccharide affinity
- 2013
-
Ingår i: Glycobiology. - : Oxford University Press (OUP). - 0959-6658 .- 1460-2423. ; 23:1, s. 59-68
-
Tidskriftsartikel (refereegranskat)abstract
- Bacteriophage HK620 recognizes and cleaves the O-antigen polysaccharide of Escherichia coli serogroup O18A1 with its tailspike protein (TSP). HK620TSP binds hexasaccharide fragments with low affinity, but single amino acid exchanges generated a set of high-affinity mutants with submicromolar dissociation constants. Isothermal titration calorimetry showed that only small amounts of heat were released upon complex formation via a large number of direct and solvent-mediated hydrogen bonds between carbohydrate and protein. At room temperature, association was both enthalpy- and entropy-driven emphasizing major solvent rearrangements upon complex formation. Crystal structure analysis showed identical protein and sugar conformers in the TSP complexes regardless of their hexasaccharide affinity. Only in one case, a TSP mutant bound a different hexasaccharide conformer. The extended sugar binding site could be dissected in two regions: first, a hydrophobic pocket at the reducing end with minor affinity contributions. Access to this site could be blocked by a single aspartate to asparagine exchange without major loss in hexasaccharide affinity. Second, a region where the specific exchange of glutamate for glutamine created a site for an additional water molecule. Side-chain rearrangements upon sugar binding led to desolvation and additional hydrogen bonding which define this region of the binding site as the high-affinity scaffold.
|
|
| 9. |
- Melani, Rafael D., et al.
(författare)
-
The Blood Proteoform Atlas : A reference map of proteoforms in human hematopoietic cells
- 2022
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 375:6579, s. 411-
-
Tidskriftsartikel (refereegranskat)abstract
- Human biology is tightly linked to proteins, yet most measurements do not precisely determine alternatively spliced sequences or posttranslational modifications. Here, we present the primary structures of similar to 30,000 unique proteoforms, nearly 10 times more than in previous studies, expressed from 1690 human genes across 21 cell types and plasma from human blood and bone marrow. The results, compiled in the Blood Proteoform Atlas (BPA), indicate that proteoforms better describe protein-level biology and are more specific indicators of differentiation than their corresponding proteins, which are more broadly expressed across cell types. We demonstrate the potential for clinical application, by interrogating the BPA in the context of liver transplantation and identifying cell and proteoform signatures that distinguish normal graft function from acute rejection and other causes of graft dysfunction.
|
|
| 10. |
- Penha, Frederico M., et al.
(författare)
-
In Situ Observation of Epitaxial Growth during Evaporative Simultaneous Crystallization from Aqueous Electrolytes in Droplets
- 2021
-
Ingår i: Crystals. - : MDPI AG. - 2073-4352. ; 11:9, s. 1122-1122
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, crystallization phenomena were investigated by real-time in situ observation of seeded droplets under evaporation using a self-developed hot-stage platform. Ternary solutions at eutonic conditions at 25 °C were investigated for the following systems: NaCl–KCl–H2O, NaCl–CaSO4–H2O, and NaCl–Na2SO4–H2O. Evidence of epitaxial growth was found for aqueous NaCl–KCl and aqueous NaCl–Na2SO4. Sodium chloride nucleated and grew epitaxially upon the other substrates in a larger proportion compared with the inverse. This observation could be related to the higher solubility, and consequently higher residual supersaturation of NaCl regarding the other components. Hopper-like NaCl crystals developed in almost all systems. The results may help devise strategies to control particle morphologies and purity in industrial crystallization from complex systems.
|
|
| 11. |
|
|
