No image available
· 2013
Crystal growth is the key step of a great number of very important applications. The development of new devices and products, from the traditional microelectronic industry to pharmaceutical industry and many others, depends on crystallization processes. The objective of this book is not to cover all areas of crystal growth but just present, as specified in the title, important selected topics, as applied to organic and inorganic systems. All authors have been selected for being key researchers in their field of specialization, working in important universities and research labs around the world. The first section is mainly devoted to biological systems and covers topics like proteins, bone and ice crystallization. The second section brings some applications to inorganic systems and describes more general growth techniques like chemical vapor crystallization and electrodeposition. This book is mostly recommended for students working in the field of crystal growth and for scientists and engineers in the fields of crystalline materials, crystal engineering and the industrial applications of crystallization processes.
No image available
· 2019
Abstract: Relaxases of the MOBH family are often found on large plasmids, genetic islands and integrative conjugative elements. Many members of this family contain an N-terminal relaxase domain (TraI_2) followed by a disordered middle part and a C-terminal domain of unknown function (TraI_2_C). The TraI_2 domain contains two putative metal-binding motifs, an HD domain motif and an alternative 3H motif. TraI, encoded within the gonococcal genetic island of Neisseria gonorrhoeae, is the prototype of the MOBH family. SAXS experiments showed that TraI_2 and TraI_2_C form globular structures separated by an extended middle domain. The TraI_2 domain cleaves oriT-ssDNA in a site-specific Mn2+ or Co2+ dependent manner. The minimal oriT encompasses 50 nucleotides, requires an inverted repeat 3′ of the nic-site and several nucleotides around nic for efficient cleavage. Surprisingly, no stable covalent relaxase-DNA intermediate was observed. Mutagenesis of conserved tyrosines showed that cleavage was abolished in the Y212A mutant, whereas the Y212F and Y212H mutants retained residual activity. The HD and the alternative 3H motifs were essential for cleavage and the HD domain residues D162 and D267 for metal ion binding. We propose that the active site binds two metal ions, one in a high-affinity and one in a low-affinity site
No image available
In modern research and development, materials manufacturing crystal growth is known as a way to solve a wide range of technological tasks in the fabrication of materials with preset properties. This book allows a reader to gain insight into selected aspects of the field, including growth of bulk inorganic crystals, preparation of thin films, low-dimensional structures, crystallization of proteins, and other organic compounds.