Comparative aspects of development and differentiation in actinomycetes.

Streptomyces viridochromogenes was grown both as submerged and surface culture. Mycelia from these cultures were analysed for the composition of lipids and fatty acids. An increase in ornithinolipid content according to incubation time was observed. The addition of phosphate inhibited the ornithinolipid synthesis. A mutant strain with bald phenotype did not exhibit the phosphate inhibition. At the same time, the mutant strain had a higher content of 12-methyltetradecanoic acid.

Section: Introductionmentioning

confidence: 99%

Fatty acid and lipid composition in mycelia from submerged or surface culture of Streptomyces viridochromogenes

Shim

1993

“…The spores of streptomycetes are resistant to lysozyme, freeze-drying and moderately resistant to heat [1,9,10]. To know whether these properties were affected by ultrasounds, suspensions of ultrasonically treated spores were assayed for their sensitivity to heat, dehydration and lysozyme attack as described above.…”

Section: Effect Of Ultrasonic Treatment On Some Properties Of the Sporesmentioning

confidence: 99%

“…The streptomycetes are filamentous bacteria with a complex developmental cycle that involves the formation, from spores, of a vegetative substrate mycelium which later differentiates to form the reproductive aerial mycelium. In liquid cultures, Streptomyces does not differentiate into aerial mycelium but grows in small aggregates containing hyphae in different physiological states [1,2]. Much of what is known on the growth and differentiation of the streptomycetes has been obtained by microscopic observations of hyphae grown on solid media [3][4][5].…”

Section: Introductionmentioning

confidence: 99%

Synchronous germination of Streptomyces antibioticus spores: Tool for the analysis of hyphal growth in liquid cultures

Miguélez

Martín

Hardisson

et al. 1993

We have devised a method for obtaining synchronous and dispersed growth of Streptomyces antibioticus in liquid cultures. After ultrasonic treatment, most of the spores germinated at the same time, yielding hyphae very similar in length. Dispersed growth was achieved in media without Ca2+ and in which the levels of Fe2+ and Mg2+ were carefully controlled. Studies on the kinetics of growth carried out with synchronous cultures of young hyphae revealed a multiphasic pattern of hyphal elongation, with successive periods of linear growth and changes in growth rate at defined intervals.

“…Information of this kind is as yet limited to ribosomal proteins from a very few bacteria, mainly unicellular bacteria belonging to the families Enterobacteriaceae [2,4,7] and Bacillaceae [4]. The streptomycetes are a group of prokaryotes 0378-1097/87/$03.50 © 1987 Federation of European Microbiological Societies which have been considered by some authors as an interesting example of convergent evolution between prokaryotic bacteria and eukaryotic fungi [9][10][11]. In the present investigation we have undertaken a comparative study of the protein composition of the ribosomes of several Streptomyces species using PAGE and a recently introduced application of HPLC to the separation of ribosomal proteins.…”

Section: Introductionmentioning

confidence: 99%

Heterogeneity of the ribosomal protein pattern in mycelium of Streptomyces species

Fierro

Parra

Quirós

et al. 1987

The pattern of ribosomal proteins of 7 Streptomyces species was studied. Proteins were separated by polyacrylamide gel electrophoresis (PAGE) using two different electrophoretic systems, and also by reverse‐phase high‐performance liquid chromatography (HPLC). By these 3 methods, clear differences were observed, in several proteins (absent in some species and present in others), with some species showing more closely related ribosomal protein patterns than others. It is suggested that the application of the present methods may be of some potential in a taxonomic context.