الفهرس 
The lichens
Comparison of lichenforming cyanobacterial and green algal photobionts with free-living algaeOnly 14 pages are availabe for public view
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Abstract
Lichen is a symbiotic relationship between a fungal partner (mycobiont) and one or more photosynthetic partners (photobiont), which may be either a green alga or a cyanobacterium. In all lichens the mycobiont composes the largest portion of the lichen thallus while the photobiont forms a small portion as an outer part of the medullary layer in the thallus. Lichens synthesize a diversity of secondary metabolites and most lichen substances are small aromatic polyketides synthesized by a polyketide synthase (PKS) in the fungal partner of the symbiosis. Photobionts produce different sugars from photosynthesis where green algal photobionts produce polyols and cyanobacterial photobionts produce glucose. These sugars provide carbon for fungal carbon based polyketides. Although the secondary metabolic pathways are entirely present within the mycobiont, our study intended to study the effect of photobiont carbohydrates on the polyketides biosynthesis and diversities of Cladonia rangiferina culture.