title: Early events of Bacillus anthracis germination identified by time-course quantitative proteomics.
abstract: Germination of Bacillus anthracis spores involves rehydration of the spore interior and rapid degradation of several of the protective layers, including the spore coat. Here, we examine the temporal changes that occur during B. anthracis spore germination using an isobaric tagging system. Over the course of 17 min from the onset of germination, the levels of at least 19 spore proteins significantly decrease. Included are acid-soluble proteins, several known and predicted coat proteins, and proteins of unknown function. Over half of these proteins are small (less than 100 amino acids) and would have been undetectable by conventional gel-based analysis. We also identified 20 proteins, whose levels modestly increased at the later time points when metabolism has likely resumed. Taken together, our data show that isobaric labeling of complex mixtures is particularly effective for temporal studies. Furthermore, we describe a rigorous statistical approach to define relevant changes that takes into account the nature of data obtained from multidimensional protein identification technology coupled with the use of isobaric tags. This study provides an expanded list of the proteins that may be involved in germination of the B. anthracis spore and their relative levels during germination.
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109-1048, USA.
authors.forename: Pratik
authors.initials: P
authors.lastname: Jagtap
authors.forename: George
authors.initials: G
authors.lastname: Michailidis
authors.forename: Ryszard
authors.initials: R
authors.lastname: Zielke
authors.forename: Angela K
authors.initials: AK
authors.lastname: Walker
authors.forename: Nishi
authors.initials: N
authors.lastname: Patel
authors.forename: John R
authors.initials: JR
authors.lastname: Strahler
authors.forename: Adam
authors.initials: A
authors.lastname: Driks
authors.forename: Philip C
authors.initials: PC
authors.lastname: Andrews
authors.forename: Janine R
authors.initials: JR
authors.lastname: Maddock
mesh_terms: D000595:Amino Acid Sequence; D001408:Bacillus anthracis / Q000737:chemistry* / Q000502:physiology*; D001426:Bacterial Proteins / Q000032:analysis / Q000096:biosynthesis; D008969:Molecular Sequence Data; D020543:Proteome / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D040901:Proteomics / Q000379:methods; D021241:Spectrometry, Mass, Electrospray Ionization; D013171:Spores, Bacterial / Q000737:chemistry / Q000502:physiology
chemical_list: D001426:Bacterial Proteins; D020543:Proteome; C030069:spore-specific proteins, Bacillus