The targets of the Structural GenomiX (SGX) bacterial genomics project were proteins conserved in multiple prokaryotic organisms with no obvious sequence homolog in the Protein Data Bank of known structures. The outcome of this work was 80 structures, covering 60 unique sequences and 49 different genes. Experimental phase determination from proteins incorporating Se-Met was carried out for 45 structures with most of the remainder solved by molecular replacement using members of the experimentally phased set as search models. An automated tool was developed to deposit these structures in the Protein Data Bank, along with the associated X-ray diffraction data (including refined experimental phases) and experimentally confirmed sequences. BLAST comparisons of the SGX structures with structures that had appeared in the Protein Data Bank over the intervening 3.5 years since the SGX target list had been compiled identified homologs for 49 of the 60 unique sequences represented by the SGX structures. This result indicates that, for bacterial structures that are relatively easy to express, purify, and crystallize, the structural coverage of gene space is proceeding rapidly. More distant sequence-structure relationships between the SGX and PDB structures were investigated using PDB-BLAST and Combinatorial Extension (CE). Only one structure, SufD, has a truly unique topology compared to all folds in the PDB.

Medical students frequently experience moral distress. Our survey can be used to measure aspects of the learning environment as well as individual responses to the environment. The variation found among student responses warrants further investigation to determine whether students at either extreme of moral distress are at risk of burnout or erosion of professionalism.

Introduction. The TM0096 gene from Thermotoga maritima is distributed widely among microorganisms, suggesting that it performs a function indispensable for life and/or virulence. Homologs of the TM0096 protein are found in prokaryotes as well as eukaryotes, including the pathogens Yersinia pestis, Listeria, Clostridium, and Bacillus anthracis.TM0096 belongs to the NIFR3 family of proteins, named after the nifR3 gene from Rhodobacter. The biochemical functions of NIFR3 family proteins are unclear, but limited research points to a role in nitrogen metabolism. For example, the photosynthetic purple bacteria Rhodobacter capsulatus experiences an order of magnitude increase in NIFR3 expression under limiting nitrogen conditions.