Molecular symbiont

Some legume hosts have been shown to be more permissive than others for expression of hydrogenase. Host-plant mediated control of the Hup phenotype has been reported for the symbionts of pea, soybean, cowpea and common bean (Maier and Triplett 1996). The molecular basis for this effect is not yet understood. In the case... 

Three cytotoxic peptides, patellamide D (31) and lissoclinamides 4-5 (32-33) were isolated from a Great Barrier Reef specimen of L. patella and identified by interpretation of spectral data. The peptides were found within the obligate algal symbiont of the genus Prochloron [65]. Another study of the same Australian L. patella reported lissoclinamide 6 (34), in addition to lissoclinamides 4-5 (32-33) and patellamide D (31). The structure of patellamide D (31) was obtained by X-ray crystallography and its conformation compared with those obtained by molecular modelling [66]. Patellamide D (31) has been reported to be a... 

One feature of the rhizobium-legume symbiosis is the high degree of specificity that many legumes and their symbiotic partners exhibit. For example, Sinorhizobium meliloti, the well-characterized bacterial symbiont of alflalfa and related Medicago species, is unable to nodule its close relative Pisum sativum (Mendel s pea), and conversely pea symbionts do not nodulate Medicago species. It is now clear that there are multiple molecular determinants... 

The biosynthetic origin of marine natural products is a complex topic that has gained more clarity through application of molecular biological study microbial symbionts may represent the true source in many sponges, ascidians, and bryozoans, even in cases in which localization studies have suggested an invertebrate source for... 

All members of this group are thought to be ectomycorrhizal or orchid symbionts [398]. The phylogenetic relationship to the Bankeraceae (Phellodon) awaits further molecular studies. So far only dolipores with perforate parenthe-somes are known in the Thelephorales [399, 400]. 

DePriest PT. Early molecular investigations of lichen-forming symbionts 1986-2001. Annu. Rev. Microbiol. 2004 58 273-301. 

Dale C, Moran NA. Molecular interactions between bacterial symbionts and their hosts Review. Cell 2006 126 453-465. 

In summary, the marine environment contains a wealth of plants, animals and microorganisms. Due to their unique adaptations to their ocean habitat, they contain a wide diversity of natural products. These compounds have shown activity in a variety of assays which have relevance to human diseases. As our understanding of the molecular basis of disease expands, these compounds and ones yet to be discovered will provide lead compounds for human therapeutic treatment. Innovations in synthesis, fermentation of symbionts as well as in manipulation of biosynthetic genes will allow us to produce sufficient material for clinical use of the compounds. Marine organisms provide a unique opportunity for access to chemical diversity. 

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