Streptomyces sporulation

Sterile agar slants are prepared using the Streptomyces sporulation medium of Hickey and Tresner, J. Bact., vol. 64, pages 891-892 (1952). Four of these slants are inoculated with lyophilized spores of Streptomyces antibioticus NRRL 3238, incubated at 28°C for 7 days or until aerial spore growth is well-advanced, and then stored at 5°C. The spores from the four slants are suspended in 40 ml of 0.1% sterile sodium heptadecyl sulfate solution. A nutrient medium having the following composition is then prepared 2.0% glucose monohydrate 1.0% soybean meal, solvent extracted, 44% protein 0.5% animal peptone (Wilson s protopeptone 159) 0.2% ammonium chloride 0.5% sodium chloride 0.25% calcium carbonate and water to make 100%. 

Antibiotic production and morphological differentiation (formation of aerial mycelium and sporulation) in Streptomyces species and in some other actinomycetes is regulated by small signaling molecules called y-butyrolactones or butanolids. These quorum-sensing signals bind to... 

Noens EE, Mersinias V, Traag BA, Smith CP, Koerten HK, van Wezel GP, SsgA-like proteins determine the fate of peptidoglycan during sporulation of Streptomyces coelicolor, Mol Microbiol 58 929—944, 2005. 

McCormick JR, Losick R, Cell division gene jfeQis required for efficient sporulation but not growth and viability in Streptomyces coelicolor A3 2), J Bacterial 178 5295-5301, 1996. 

Daza A, Martin JF, Dominguez A, Gil JA, Sporulation of several species of Streptomyces in submerged cultures after nutritional downshift, J Gen Microbiol... 

J Hao, KE Kendrick. Visualization of penicillin-binding proteins during sporulation of Streptomyces griseus. J Bacteriol 180 2125-2132, 1998. 

The medium is cooled and inoculated with 20 ml of a suspension of the spores from two Mover s sporulation agar slant cultures of Streptomyces rimosus forma paromomycinus in sterile 0.1% sodium heptadecyl sulfate solution. The inoculated culture mixture is incubated at 26°C for sixty hours during which time the mixture is stirred at 200 rpm and sterile air is passed into the medium through the sparger at the rate of 12 liters per minute. A portion of the resulting incubated culture mixture is employed for inoculation of 16 liters of a nutrient medium having the following composition ... 

The Streptomyces WEC 85E assay has been used to test fermentation extracts from two thousand actinomycete isolates. Over one himdred strains, representing possibly twenty-seven different species, were foimd to produce metabolites that affect the onset of sporulation. Purification and characterization of the active metabolites present in some of these extracts is currently in progress. 

Activities of various signal transduction inhibitors on sporulation of Streptomyces strain WEC 85E... 

Despite the apparent connections between formation of antibiotics and spores, it has become clear that antibiotic production is not obligatory for spore formation [192]. The most damaging evidence to the antibiotic-spore obligatory hypothesis is the existence of mutants which form no antibiotic but still sporulate. Such mutants have been found in the cases of bacitracin (Bacillus licheniformis), myco-bacillin (Bacillus subtilis), linear gramicidin (B. brevis), tyrocidine (B. brevis), gramicidin S (B. brevis), oxytetracycline (Streptomyces rimosus), streptomycin (S. griseus), methylenomycin A (Streptomyces coelicolor), and patulin (Penicillium urticae). 

In the biochemically less sophiscated (than eukaryotes) prokaryotic cells, a regulatory role of Ca " " is not well-established. What is known is that calcium is massively accumulated during sporulation in many bacteria, for example, in strains of Bacillus, Streptomyces, and Myxococcus. In Myxococcus xanthus a development-specific protein called protein S assembles at the surface of myxos-pores in the presence of Ca. The DNA sequence of the gene that encodes this... 

Fig. 1 Photography of a sporulated Streptomyces strain growing on solid medium. The blue drops indicate the production of an antibiotic (aromatic polyketide). (See Color Plate p. xv).

Nabais AMA, da Fonseca MMR (1995) The effect of solid medium composition on growth and sporulation of Streptomyces clavuligerus spore viability dming storage at 4°C. Biotechnol Tech 9 361- 364... 

Virginiae B. are formed by Streptomyces species as antibiotic-inducing and sporulation-triggering fac-... 

Hopwood, D.A. (1988) Towards an understanding of gene switching in Streptomyces, the basis of sporulation... 

A close relationship between eporulation and secondary biosynthesis by Streptomyces kanamyceticus (14) and in Streptomyces bikiniensis was described (l5). Non-sporu-lating variants were obtained with acriflavine treatment which lost the ability to produce the antibiotics. If it is assumed that the structural genes of the biosynthetic pathway are localized in chromosome, the deletion of ex-trachromosomal DNA may cause a loss of the ability to produce an endogenous inducer. Induction of the enzymes governing the formation of secondary metabolites would thus be closely associated with the expression of other traits, particularly sporulation. This fact was observed by Drew et al. (16) induction of cephalosporin C formation in Cephalosporium acremonium by methionine was ac-companied by arthrospore formation. 

Tian Z, Cheng Q, Yoshimoto FK, Lei L, Lamb DC, Guengerich FP (2013) Cytochrome P450 107U1 is required for sporulation and antibiotic production in Streptomyces coelicolor. Arch Biochem Biophys 530 101-107... 

A Streptomyces inhibitor blocked sporulation of B. subtilis presumably by selective inhibition of a membrane bound protease. The latter was postulated to degrade the B. subtilis protease inhibitor and thus indirectly modulate the level of intracellular protease activity and consequently, sporulation. Burnett et al. [5] found that a substantial fraction of the B. subtilis intracellular protease activity was cryptic i.e. antigen was in excess of activity early in sporulation when protease inhibitor activity was highest. This correlation was also consistent with a function for the inhibitor in modulating intracellular protease. 

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