Peptide name : Laxaphycin A

Source/Organism : Terrestrial blue-green alga or the marine cyanobacterium

Linear/Cyclic : Cyclic

Chirality : L

Peptide length: Not available

C-terminal modification: Cyclic

N-terminal modification : Free

Non-natural peptide information: Aoc : 3-aminooctanoic acid ,Hyp : 4- hydroxyproline, Dhb : didehydrobutyrine, Hse : Homoserine

Assay type : Cell viability assay

Assay time : 96h

Activity : No inhibition at 4 µM

Cell line : CEM-VLB

Cancer type : Leukemia cancer

Other activity : Anti-fungal property

Amino Acid Composition Bar Chart : Not available

Molecular mass : Not available

Aliphatic index : Not available

Instability index : Not available

Hydrophobicity (GRAVY) : Not available

Isoelectric point : Not available

Charge (pH 7) : Not available

Aromaticity : Not available

Molar extinction coefficient (cysteine, cystine): Not available

Hydrophobic/hydrophilic ratio : Not available

hydrophobic moment : Not available

Missing amino acid : Not available

Most occurring amino acid : Not available

Most occurring amino acid frequency : Not available

Least occurring amino acid : Not available

Least occurring amino acid frequency : Not available

3D-structure: Not available

Secondary structure fraction (Helix, Turn, Sheet): Not available

SMILES Notation: Not available

Molecular descriptors: Not available

ADMET properties: Not available

1 : Gbankoto A, et al. Cytotoxic effect of Laxaphycins A and B on human lymphoblastic cells (CCRF-CEM) using digitised videomicrofluorometry. In Vivo. 2005; 19:577-82.

2 : Frankmölle WP, et al. Antifungal cyclic peptides from the terrestrial blue-green alga Anabaena laxa. II. Structures of laxaphycins A, B, D and E. J Antibiot (Tokyo). 1992; 45:1458-66. doi: 10.7164/antibiotics.45.1458

Paper title : Cytotoxic effect of Laxaphycins A and B on human lymphoblastic cells (CCRF-CEM) using digitised videomicrofluorometry.

Doi : https://doi.org/Not available

Abstract : Laxaphycin A (laxa A) and Laxaphycin B (laxa B), cyclic peptides isolated from the terrestrial blue-green alga Anabaena laxa or the marine cyanobacterium Lyngbya majuscula have antifungal and cytotoxic activities. We used numerical videomicrofluorometry and a protocol of multiple labelling with Hoescht 33342 (nuclear DNA), Rhodamine 123 (mitochondria) and Nile Red (plasma membrane) to study the cytotoxicity of these substances in human lymphoblastic cells sensitive (CEM-WT) or resistant (CEM-VLB and CEM-VM1) to anticancer agents. The results indicate a low resistance index of 2 for CEM-VLB cells treated with laxa B or laxa A + lava B. For the three cell strains, following laxa B treatment, we observed an increase of a polyploid cell subpopulation that could result from the alteration of topoisomerase-II activity. On the contrary, the simultaneous treatment by laxa A and laxa B led to a decrease of that subpopulation with increasing laxa A doses. However, the effect of laxa A was less pronounced in the CEM-VM1 cells, which present a low intrinsic topoisomerase-II activity. For CEM-VLB cells, the higher doses needed can be attributed to their MDR resistance. Though we observed a synergistic effect between laxa B and laxa A (the latter is inactive by itself), these results indicate a different mode of action for laxa B and laxa A + laxa B. A more precise study of the mode of action of these compounds is warranted.

Paper title : Antifungal cyclic peptides from the terrestrial blue-green alga Anabaena laxa. II. Structures of laxaphycins A, B, D and E.

Doi : https://doi.org/10.7164/antibiotics.45.1458

Abstract : Laxaphycins A and B are the major components in an antifungal mixture of cyclic peptides from the terrestrial blue-green alga Anabaena laxa FK-1-2. NMR and MS spectral studies coupled with amino acid analysis indicate that the gross structures of laxaphycins A and B are cyclic (Aoc-Hse-E-Dhb-Hyp-Hse-Phe-Leu-Ile-Ile-Leu-Gly) where Aoc is a 3-aminooctanoic acid residue and cyclic (Ala-Hleu-Gln-N-MeIle-Hasn-Thr-Pro-Leu-Thr-Ade-Val- Hleu) where Ade is a 3-aminodecanoyl unit, respectively. Laxaphycin E, a minor cyclic undecapeptide, differs in gross structure from laxaphycin A in possessing a 3-aminodecanoic acid unit (Ade) in lieu of Aoc, whereas laxaphycin D, a minor cyclic dodecapeptide, differs from laxaphycin B in possessing a 3-aminooctanoyl unit (Aoc) instead of an Ade unit.