Characterization of the Mucor circinelloides life cycle by on-line image analysis.
OBJECTIVE
The life cycle of the dimorphic fungus Mucor circinelloides was studied in a temperature-controlled flow-through cell, which constitutes an ideal tool when following the development of individual cells, with a view to understanding the growth and differentiation processes occurring in and between the different morphological forms of the organism.


RESULTS
Mycelial growth and the transformation of hyphae into chains of arthrospores were characterized by image analysis techniques and described quantitatively. The influence of the nature (glucose and xylose) and concentration of the carbon source on specific growth rate and hyphal growth unit length were studied. The organism branched more profusely on xylose than on glucose while the specific growth rates determined were rather similar. Methods were developed to study the yeast-like growth phase of M. circinelloides in the flow-through cell, and combined with fluorescent microscopy which allowed new insights to bud formation. Additionally, numbers and distribution of nuclei in arthrospores, hyphae and yeasts were studied.


CONCLUSIONS
The results give essential information on the morphological development of the organism.


CONCLUSIONS
Development of any industrial process utilizing this organism will be dependent on the information obtained here for effective process optimization.
Lübbehüsen
T L
TL
Center for Process Biotechnology, BioCentrum-DTU, Building 223, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Nielsen
J
J
McIntyre
M
M
D002467:Cell Nucleus / Q000648:ultrastructure; D003470:Culture Media; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000494:pharmacology; D007091:Image Processing, Computer-Assisted / Q000379:methods; D008856:Microscopy, Fluorescence; D009089:Mucor / Q000187:drug effects / Q000254:growth & development* / Q000648:ultrastructure; D013172:Spores, Fungal / Q000254:growth & development; D013696:Temperature; D014994:Xylose / Q000494:pharmacology
D003470:Culture Media; D014994:Xylose; D005947:Glucose