Aerial hyphae in surface cultures of Streptomyces lividans and Streptomyces coelicolor originate from viable segments surviving an early programmed cell death event.
Morphogenesis in streptomycetes is characterized by the formation of aerial hyphae that emerge from the substrate mycelium. Despite many years of study, a detailed picture of the events that occur during the transition from substrate to aerial mycelium has yet to be defined. In this paper, it was shown that a specific cell death event takes place during early growth of the substrate mycelium in Streptomyces coelicolor and Streptomyces lividans. Subsequently, a second mycelium starts to develop from the remaining viable segments of these substrate hyphae in the form of islands, which progressively cover the plate surface. Interestingly, the genes coding for the chaplin and rodlin proteins, which are involved in the formation of the hydrophobic layer characteristic of aerial structures, are specifically expressed in the second mycelium islands, strongly suggesting that this second mycelium should be considered the early precursor of the mature hydrophobic aerial mycelium.
Departamento de Biologia Funcional e Instituto de Biotecnologia de Asturias (IUBA), Universidad de Oviedo, Oviedo, Spain.
Angel
A
Manteca
Dennis
D
Claessen
Carmen
C
Lopez-Iglesias
Jesus
J
Sanchez
D017209:Apoptosis; D001426:Bacterial Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D049452:Green Fluorescent Proteins / Q000032:analysis; D013171:Spores, Bacterial / Q000254:growth & development; D048372:Streptomyces coelicolor / Q000166:cytology / Q000254:growth & development* / Q000502:physiology; D048170:Streptomyces lividans / Q000166:cytology / Q000254:growth & development* / Q000502:physiology
D001426:Bacterial Proteins; D049452:Green Fluorescent Proteins