J Bacteriol 2010,192(15):3883–3892.PubMedCrossRef 37. Carter JH, Du Bus RH, Dyer JR, Floyd JC, Rice KC, Shaw PD: Biosynthesis of viomycin. II. Origin of beta-lysine and viomycidine. Biochemistry 1974,13(6):1227–1233.PubMedCrossRef 38. Carter JH,

Du Bus RH, Dyer Sapitinib chemical structure JR, Floyd JC, Rice KC, Shaw PD: Biosynthesis of viomycin. I. Origin of alpha, beta-diaminopropionic acid and serine. Biochemistry 1974,13(6):1221–1227.PubMedCrossRef 39. Lam WH, Rychli K, Bugg TD: Identification of a novel beta-replacement reaction in the biosynthesis of 2,3-diaminobutyric acid in peptidylnucleoside mureidomycin A. Org Biomol Chem 2008, 6:1912–1917.PubMedCrossRef Authors’ contributions FCB and JC carried out the molecular genetic and bioinformatics studies and drafted the manuscript. All authors participated in the Akt activator design of the study, and edited and approved the final version of the manuscript.”
“Background Spore-forming Bacilli are aerobic, Gram positive organisms sharing a common attribute of being able to differentiate into an endospore (spore), a quiescent cell form characterized by several protective layers surrounding a dehydrated cytoplasm [1]. This structural organization makes the spores extremely resistant to external physical and chemical

insults and able to survive almost indefinitely in the absence of water and nutrients [1]. The soil is generally indicated as the main habitat of aerobic spore-formers, however, spores have been found in diverse environments including rocks, dust, aquatic environments, and the gut

of various insects and animals [2]. Recent reports have highlighted the fact that large numbers of aerobic spore-formers can be isolated from fecal and intestinal samples of healthy animals [3, 4], including humans [5, 6]. Hong and colleagues [2] have reported that an average of 104 colony forming units (CFU) of aerobic spore-formers are isolated from human feces collected in different countries and from people with different dietary habits. These PDK4 observations, together with a series of reports indicating that B. subtilis, the model system for spore-formers, can conduct its entire life cycle in the animal gut [7, 8], have suggested the hypothesis that the gut is the real habitat of spore-formers [9]. These spore-forming bacteria would enter the mammalian GI-tract in the spore form, safely transit across the stomach, germinate and grow in the upper part of the small intestine, sporulate in the lower part of the intestine and finally be excreted in the spore form [9]. It has long been known that some aerobic Bacilli are pigmented and examples include strains of B. megaterium [10], B. atrophaeus [11], B. indicus [12], B. cibi [13], B. vedderi [14], B. jeotgali [15], B. okuhidensis [16], B. clarkii [17], B. pseudofirmus [17] and B. firmus [18]. More recently, a large number of pigmented Bacilli have been isolated and their pigments identified as carotenoids [19].