title: Genome analysis of the meat starter culture bacterium Staphylococcus carnosus TM300.
abstract: The Staphylococcus carnosus genome has the highest GC content of all sequenced staphylococcal genomes, with 34.6%, and therefore represents a species that is set apart from S. aureus, S. epidermidis, S. saprophyticus, and S. haemolyticus. With only 2.56 Mbp, the genome belongs to a family of smaller staphylococcal genomes, and the ori and ter regions are asymmetrically arranged with the replichores I (1.05 Mbp) and II (1.5 Mbp). The events leading up to this asymmetry probably occurred not that long ago in evolution, as there was not enough time to approach the natural tendency of a physical balance. Unlike the genomes of pathogenic species, the TM300 genome does not contain mobile elements such as plasmids, insertion sequences, transposons, or STAR elements; also, the number of repeat sequences is markedly decreased, suggesting a comparatively high stability of the genome. While most S. aureus genomes contain several prophages and genomic islands, the TM300 genome contains only one prophage, PhiTM300, and one genomic island, nuSCA1, which is characterized by a mosaic structure mainly composed of species-specific genes. Most of the metabolic core pathways are present in the genome. Some open reading frames are truncated, which reflects the nutrient-rich environment of the meat starter culture, making some functions dispensable. The genome is well equipped with all functions necessary for the starter culture, such as nitrate/nitrite reduction, various sugar degradation pathways, two catalases, and nine osmoprotection systems. The genome lacks most of the toxins typical of S. aureus as well as genes involved in biofilm formation, underscoring the nonpathogenic status.
authors.affiliation: Mikrobielle Genetik, Eberhard-Karls-Universität Tübingen, Germany. ralf.rosenstein@uni-tuebingen.de
authors.forename: Ralf
authors.initials: R
authors.lastname: Rosenstein
authors.forename: Christiane
authors.initials: C
authors.lastname: Nerz
authors.forename: Lalitha
authors.initials: L
authors.lastname: Biswas
authors.forename: Alexandra
authors.initials: A
authors.lastname: Resch
authors.forename: Guenter
authors.initials: G
authors.lastname: Raddatz
authors.forename: Stephan C
authors.initials: SC
authors.lastname: Schuster
authors.forename: Friedrich
authors.initials: F
authors.lastname: Götz
mesh_terms: D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics*; D016680:Genome, Bacterial; D020071:Interspersed Repetitive Sequences; D008460:Meat / Q000382:microbiology*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D039002:Prophages / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D017422:Sequence Analysis, DNA; D013210:Staphylococcus / Q000235:genetics*; D026801:Synteny
chemical_list: D004269:DNA, Bacterial