- Structure-antifungal activity relationships of cecropin a hybrid peptides against trichoderma sp.
-
Shin, Song Yub , Lee, Dong Gun , Lee, Sung gu , Kim, Kil Lyong , Lee, Myung Kyu , Hahm, Kyung Soo
-
J. Microbiol. 1997;35(1):21-24.
-
-
-
 Abstract
 PDF
-
The hybrid peptides, CA-ME, CA-MA and CA-BO, with the N-terminal sequence 1-8 of cecropin A and the N-terminal sequences 1-12 of melittin, magainin 2 and bombinin, respectively, have more improved antibacterial activities. CA-MA was found to have stronger antifungal activity against Trichoderma sp than other hybrid peptides and their parental peptides. In order to elucidate the relationships between the peptide structure and antifungal activity, several analogues of CA-MA or CA-BO were also designed and synthesized by the solid phase method. Antifungal activity was measured against T. reesei and T. viride, and hemolytic activity was measured by a solution method against human red blood cells. The residue 16 of CA-MA, Ser, was found to be important for antifungal activity. When the residue was substituted with Leu, showed powerful antifungal activity was dramatically decreased. CA-MA, P1, P4 and P5 designed in this study showed powerful antifungal activity against T. reesei and T. viride with low hemolytic activity against human red blood cells. These hybrid peptides will be potentially useful model to further design peptides with powerful antifungal activity for the effective therepy of fungal infection and understand the mechanisms of antifungal actions of hybrid peptides.
- Antifungal activities of peptides with the sequence 10-17 of magainin 2 at the N-termini against aspergillus fumigatus
-
Lee, Myung Kyu , Lee, Dong Gun , Shin, Song Yub , Lee, Sung Gu , Kang, Joo Hyun , Hahm, Kyung Soo
-
J. Microbiol. 1996;34(3):274-278.
-
-
-
Abstract
PDF
-
Two peptides, MA-inv AND MA-ME, with the sequence 10-17 of maganin 2 at their-N-termini were designed and synthesized. The peptides had higher antifungal activities against Aspergilus fumigatus without hemolytic activities. The minimal inhibition concentratory (MIC) values of both peptides against A. fumigatus were 5 ㎍/ml, whereas those of the native peptides, magainin 2 and melittin, were 10㎍/ml. At 3 ㎍/ml, MA-inv and MA-ME inhibited the mycelium growth of A. fumigatus by 94.6% and 97.3% respectively, whereas magainin 2 and melittin inhibited by 62.2% and 32.4, respectively. MA-inv showed up to 80% inhibition of (1, 3)-β-D-glucan synthase activity of A. fumigatus. The peptides also showed up to 80% inhibition of (1, 3)-β-D glucan synthase activity of A. fumigatus. The peptides also showed antifungal activities for other fungi of Aspergillus sp. However, the antibiotic activities of MA-ME against Escherichia coli, Bacillus subtilis and Fusarium oxysporum were more effective than those of MA-inv, suggesting that the C-terminal sequences of MA-inv and MA-ME may also influence their antibiotic activities. These results suggest that the N-terminal sequence of the designed peptides, KKFGKAFV, is important for their antifungal activities against A. fumigatus and their C- terminal sequences are related to the organism selectivity.
|
MSK
