ABSTRACT
To estimate the minimal gene set required to sustain bacterial life in nutritious conditions, we carried out a systematic inactivation of Bacillus subtilis genes. Among approximately 4,100 genes of the organism, only 192 were shown to be indispensable by this or previous work. Another 79 genes were predicted to be essential. The vast majority of essential genes were categorized in relatively few domains of cell metabolism, with about half involved in information processing, one-fifth involved in the synthesis of cell envelope and the determination of cell shape and division, and one-tenth related to cell energetics. Only 4% of essential genes encode unknown functions. Most essential genes are present throughout a wide range of Bacteria, and almost 70% can also be found in Archaea and Eucarya. However, essential genes related to cell envelope, shape, division, and respiration tend to be lost from bacteria with small genomes. Unexpectedly, most genes involved in the Embden-Meyerhof-Parnas pathway are essential. Identification of unknown and unexpected essential genes opens research avenues to better understanding of processes that sustain bacterial life.
Subject(s)
Bacillus subtilis/genetics , Genes, Bacterial , Bacillus subtilis/cytology , Bacillus subtilis/metabolism , Cell Division/genetics , Cell Membrane/genetics , Coenzymes/genetics , Coenzymes/metabolism , Energy Metabolism/genetics , Genome, Bacterial , Mutation , Nucleotides/genetics , Nucleotides/metabolism , PhylogenyABSTRACT
Although there is evidence to suggest that breast self-examination (BSE) aids in the early detection of breast cancer, the underuse of this prevention behavior continues to exist. The purpose of this study was to explore the personal behaviors and professional practices of nurses in the use of BSE and to discuss implications for the advanced practice nurse (APN). The sample (N = 300) consisted of nurses and student nurses. While almost all nurses had performed BSE at least once, fewer than half did this monthly. The majority believed it was the nurse's role to teach BSE, but almost three fourths of the sample taught it only occasionally or rarely. Not thinking of it and not knowing when or how to teach were reasons identified for not teaching. The roles of the APN as an educator, leader, consultant, direct care provider, and researcher are examined in light of these findings to promote nurses' performing and teaching BSE.
