Secondary metabolites from marine microorganisms

Abstract

After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

Amphritea atlantica gen. nov., sp. nov., a gammaproteobacterium from the Logatchev hydrothermal vent field

“…Hence, cultivation approaches are necessary and need to be applied. Moreover, micro-organisms from extreme marine environments are considered as a rich source for the detection of new secondary metabolites, new metabolic pathways and new enzymes and therefore have become a special focus of research in recent years (Faulkner, 2000;Haefner, 2003;Jensen & Fenical, 1994;Kelecom, 2002).As part of a study of the microbial biodiversity of hydrothermal vents in the Mid-Atlantic Ridge, we have isolated numerous bacteria living in habitats influenced by hydrothermal activity. Among these, a novel Gramnegative, mesophilic, rod-shaped gammaproteobacterium, strain M41 T , showed less than 94 % 16S rRNA gene sequence similarity to any other recognized bacterium.…”

“…Hence, cultivation approaches are necessary and need to be applied. Moreover, micro-organisms from extreme marine environments are considered as a rich source for the detection of new secondary metabolites, new metabolic pathways and new enzymes and therefore have become a special focus of research in recent years (Faulkner, 2000;Haefner, 2003;Jensen & Fenical, 1994;Kelecom, 2002).…”

Antimycobacterial activity of cyclic dipeptides isolated fromBacillussp. N strain associated with entomopathogenic nematode

“…DKPs comprise an important family of the secondary metabolites that are mainly produced by microorganisms (Kelecom, 2002). They are the smallest possible cyclic peptides.…”

Organismos marinhos como fonte de novos fármacos: histórico & perspectivas

“…Ora, assim como já foram isoladas substâncias quimicamente semelhantes a partir de organismos filogeneticamente distantes, outras originadas por vias biossintéticas completamente distintas achavam-se presentes numa mesma espécie. 85 O potencial dos micro-organismos marinhos na busca de novos fármacos é também fundamentado na importância histórica dos microorganismos terrestres como fonte de fármacos. A rigor, algum esforço já foi empreendido neste sentido e inúmeros metabólitos secundários interessantes já foram isolados a partir desses grupos, mas presume-se que ainda haja um desmesurado número de substâncias por descobrir.…”