Mycelium differentiation and development of Streptomyces coelicolor in lab-scale bioreactors: programmed cell death, differentiation, and lysis are closely linked to undecylprodigiosin and actinorhodin production.
Streptomycetes are mycelium-forming bacteria that produce two thirds of clinically relevant secondary metabolites. Secondary metabolite production is activated at specific developmental stages of Streptomyces life cycle. Despite this, Streptomyces differentiation in industrial bioreactors tends to be underestimated and the most important parameters managed are only indirectly related to differentiation: modifications to the culture media, optimization of productive strains by random or directed mutagenesis, analysis of biophysical parameters, etc. In this work the relationship between differentiation and antibiotic production in lab-scale bioreactors was defined. Streptomyces coelicolor was used as a model strain. Morphological differentiation was comparable to that occurring during pre-sporulation stages in solid cultures: an initial compartmentalized mycelium suffers a programmed cell death, and remaining viable segments then differentiate to a second multinucleated antibiotic-producing mycelium. Differentiation was demonstrated to be one of the keys to interpreting biophysical fermentation parameters and to rationalizing the optimization of secondary metabolite production in bioreactors.
Área de Microbiología, Departamento de Biología Funcional e IUOPA, Facultad de Medicina, Universidad de Oviedo, 33006 Oviedo, Spain.
Beatriz
B
Rioseras
María Teresa
MT
López-García
Paula
P
Yagüe
Jesús
J
Sánchez
Angel
A
Manteca
D000880:Anthraquinones / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000096:biosynthesis; D017209:Apoptosis; D061249:Batch Cell Culture Techniques; D019149:Bioreactors / Q000382:microbiology*; D005285:Fermentation; D025282:Mycelium / Q000166:cytology* / Q000254:growth & development*; D011353:Prodigiosin / Q000031:analogs & derivatives* / Q000096:biosynthesis; D048372:Streptomyces coelicolor / Q000166:cytology / Q000254:growth & development*; D013997:Time Factors; D000095622:Benzoisochromanequinones
D000880:Anthraquinones; D000900:Anti-Bacterial Agents; D011353:Prodigiosin; C047347:undecylprodigiosin; C013390:actinorhodin; D000095622:Benzoisochromanequinones
Antibiotics; Bioreactor; DOT; Differentiation; MI; MII; OTR; OUR; PCD; PI; PMT; Programmed cell death; Streptomyces; dissolved oxygen tension; first compartmentalized mycelium; oxygen transfer rates; oxygen uptake rate; photomultiplier tube; programmed cell death; propidium iodide; second multinucleated mycelium