http://hdl.handle.net/10362/3555 Sat, 18 May 2013 08:04:09 GMT 2013-05-18T08:04:09Z http://hdl.handle.net/10362/5842 Title: Novel Secretion Apparatus Maintains Spore Integrity and Developmental Gene Expression in Bacillus subtilis Authors: Doan, T.; Morlot, C.; Meisner, J.; Serrano, M.; Henriques, A. O.; Moran, C. P.; Rudner, D. Z. Abstract: Sporulation in Bacillus subtilis involves two cells that follow separate but coordinately regulated developmental programs. Late in sporulation, the developing spore (the forespore) resides within a mother cell. The regulation of the forespore transcription factor sigma(G) that acts at this stage has remained enigmatic. sigma(G) activity requires eight mother-cell proteins encoded in the spoIIIA operon and the forespore protein SpoIIQ. Several of the SpoIIIA proteins share similarity with components of specialized secretion systems. One of them resembles a secretion ATPase and we demonstrate that the ATPase motifs are required for sigma(G) activity. We further show that the SpoIIIA proteins and SpoIIQ reside in a multimeric complex that spans the two membranes surrounding the forespore. Finally, we have discovered that these proteins are all required to maintain forespore integrity. In their absence, the forespore develops large invaginations and collapses. Importantly, maintenance of forespore integrity does not require sigma(G). These results support a model in which the SpoIIIA- SpoIIQ proteins form a novel secretion apparatus that allows the mother cell to nurture the forespore, thereby maintaining forespore physiology and sigma(G) activity during spore maturation. Description: Plos Genetics, 5(7): ARTe1000566 Thu, 01 Jan 2009 00:00:00 GMT http://hdl.handle.net/10362/5842 2009-01-01T00:00:00Z http://hdl.handle.net/10362/5790 Title: Metabolic and morphogenetic engineering of Bacillus subtilis: biotechnology for industry Authors: Potot, Sébastien Abstract: The bacterium Bacillus subtilis plays a major role as model for Gram-positive research, and is widely used as industrial workhorse for the production of high-value enzymes and metabolites. Successful development of commercially-attractive strains and of original products is the key of innovation in microbial industry. Evolving a natural B. subtilis strain into an overproducer involves genetic engineering. In spite of a wide range of genetic tools and techniques available for B. subtilis, engineering of the metabolic pathways, with the purpose to reach industrially significant amount of products, requires a deep and specific understanding of the metabolism.(...) Description: Dissertation presented to obtain the Ph.D. degree in “Biology” at the Institute of Chemical and Biological Technology of the New University of Lisbon Mon, 01 Nov 2010 00:00:00 GMT http://hdl.handle.net/10362/5790 2010-11-01T00:00:00Z