Two Novel Cyclic Peptides with Antifungal Activity from the Cyanobacterium Tolypothrix byssoidea (EAWAG 195)

Abstract

Two novel cyclic tridecapeptides, tolybyssidins A (1) and B (2), were isolated from the culture medium of mass cultured cyanobacterium Tolypothrix byssoidea (EAWAG 195) by means of bioguided isolation. The gross structures of these peptides were determined by 1D and 2D NMR experiments and tandem mass spectrometry. Both peptides contain the nonnatural amino acid dehydrohomoalanine (Dhha) as well as proteinogenic amino acids albeit with D- or L-configuration. The compounds exhibit moderate antifungal activity against the yeast Candida albicans.

Allelopathic activity of the norharmane-producing cyanobacterium Synechocystis aquatilis against cyanobacteria and microalgae

“…These results are thus in accordance with those obtained in other studies, i.e. finding that norharmane and nostocarboline are produced within cells and released from cyanobacterial cells into the environment during the growth (Jaki et al 2000(Jaki et al , 2001Volk 2005Volk , 2007Blom et al 2006).The production and release of norharmane by the cyanobacterium S. aquatilis into medium, could likely occur in the natural environment, and thus affect other organisms co-occurring in the same habitat. In the present study, two methods were applied to assess the allelopathic activity of this cyanobacterium on the representative species of cyanobacteria and green algae.…”

“…Cyanobacteria are well known to produce a wide range of secondary metabolites with allelopathic activities including antialgal, antibiotic, antifungal and anti-predator activities are allelopathic compounds (Smith, Doan 1999;Gross 2003;Legrand et al 2003). These allelochemicals are released into the environment during algal growth or at cell lysis (Jaki et al 2001).…”

In vivo Evaluation of Antimicrobial Effect of Methanolic Extract of Chlorella vulgaris on Impetigo and Some Dermatophytes

“…Jaki et al (2000) determined the structure of five novel extracellular di-terpenoids with biological activity from the cyanobacterium N. commune by spectroscopic methods, mainly NMR and MR. Furthermore, Jaki et al (2001) determined the structure of two novel cyclic peptides with antifungal activity from the cyanobacterium Tolypothrix by 1D and 2D NMR experiments and tandem mass spectrometry.…”

Biological activity of microalgae can be enhanced by manipulating the cultivation temperature and irradiance

“…Nostoc commune diterpenoids antibacterial, molluscicidal [7] Anabaena constricta indole alkaloid antimicrobial [8] Tolypotrix byssoidea peptides antifungal [9] Fischerella ambigua "parsiguine" antibacterial, antifungal [10] Brazilian isolates nonribosomal peptides antimicrobial [11] Synechocystis sp. Gracilaria lemaneiformis R-phycoerythrin free radicals scavenger, antitumor [42] suppressing effect on MCF-7 cancer cells even at a very low concentration (0.1 μg mL -1 ) [33].…”