𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Microscale structure and function of anaerobic–aerobic granules containing glycogen accumulating organisms

✍ Scribed by Rikke Louise Meyer; Aaron Marc Saunders; Raymond Jianxiong Zeng; Jürg Keller; Linda Louise Blackall


Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
618 KB
Volume
45
Category
Article
ISSN
0168-6496

No coin nor oath required. For personal study only.

✦ Synopsis


The spatial arrangement and metabolic activity of 'Candidatus Competibacter phosphatis' was investigated in granular sludge from an anaerobic-aerobic sequencing batch reactor enriched for glycogen-accumulating organisms. In this process, the electron donor (acetate) and the electron acceptor (oxygen) were supplied sequentially in each phase. The organism, identified by fluorescence in situ hybridisation, was present throughout the granules; however, metabolic activity was limited to a 100-mum-thick layer immediately below the surface of the granules. To investigate the cause of this, oxygen microsensors and a novel microscale biosensor for volatile fatty acids were used in conjunction with chemical staining for intracellular storage polymers. It was found that the limited distribution of activity was caused by mass transport limitation of oxygen into the granules during the aerobic phase.