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Kim MH Park SC Kim JY Lee SY Lim HT Cheong H Hahm KS Park Y 《Biochemical and biophysical research communications》2006,346(3):681-686
Potide-G, a small (5578.9 Da) antimicrobial peptide, was isolated from potato tubers (Solanum tuberosum L. cv. Golden Valley) through extraction of the water-soluble fraction, dialysis, ultrafiltration and DEAE-cellulose and C18 reverse-phase high performance liquid chromatography. This antimicrobial peptide was heat-stable and almost completely suppressed the proteolytic activity of trypsin, chymotrypsin and papain, with no hemolytic activity. In addition, potide-G potently inhibited growth of a variety of bacterial (Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Clavibacter michiganense subsp. michiganinse) and fungal (Candida albicans and Rhizoctonia solani) strains. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry revealed that the N-terminal sequence (residues from 1 to 11) of the protein is identical to that of potato proteinase inhibitor, a member of the Kunitz superfamily. And like other members of this class of protease inhibitor, potide-G may have a number of beneficial and therapeutic uses. 相似文献
2.
Design of novel analogues with potent antibiotic activity based on the antimicrobial peptide, HP(2-9)-ME(1-12) 总被引:2,自引:0,他引:2
To develop novel antibiotic peptides useful as therapeutic drugs, a number of analogues were designed to increase the hydrophobic helix region either by Trp-substitution or net positive charge increase by Lys-substitution, from HP(2-9)-ME(1-12). The antibiotic activities of these peptides were evaluated using bacterial (Salmonella tryphimurium, Proteus vulgaris, Bacillus subtilis and Staphylococcus aureus), fungi (Saccharomyces cerevisiae, Trichosporon beigelii and Candida albicans), tumor and human erythrocyte cells. The substitution of Lys for Thr at position 18 and 19 of HP(2-9)-ME(1-12) (HM5) increased activity against Proteus vulgaris and fungal strains without hemolysis. In contrast, substitution of Trp for Lys and Thr at positions 2, 15 and 19 of HP(2-9)-ME(1-12), respectively (HM3 and HM4), decreased activity but increased hemolysis against human erythrocytes. This suggests that an increase in positive charge increases antimicrobial activity whereas an increase in hydrophobicity by introducing Trp residues at C-terminus of HP(2-9)-ME(1-12) causes a hemolytic effect. Circular dichroism spectra suggested that the alpha-helical structure of these peptides plays an important role in their antibiotic effect but that the alpha-helical property is not connected with the enhanced antibiotic activity. 相似文献
3.
P5 (KWKKLLKKPLLKKLLKKL-NH(2)) is an antibacterial 18-mer Leu-Lys rich peptide from CA (1-8)-MA (1-12) hybrid peptide (CA-MA). Here we show that decreasing the net hydrophobicity and charge of CA-MA by deleting Leu- or Lys- of the N- or C-terminal regions of P5 (P10 or P11). The antimicrobial activity of the peptides was measured by their growth inhibitory effect upon S. aureus, B. subtilis, P. aeruginosa, S. typhimurium, E. coli, T. beigelii and C. albicans. Antimicrobial activity required a full length C-terminus. Confocal microscopy showed that P11 was located in the plasma membrane. In this study, P11, K(3)K(4)L(5)L(6)-deleted peptide, acted independent on the ionic environment. Furthermore, P11 causes significant morphological alterations of the fungal surfaces as shown by scanning electron microscopy. 相似文献
4.
Regeneration of Panax ginseng C.A. Meyer by organogenesis and nuclear DNA analysis of regenerants 总被引:1,自引:0,他引:1
Plant regeneration ability of ginseng (t Panax ginseng C.A. Meyer) via organogenesis was studied. Compact callus was induced
from four different types of explants-leaf, petiole, flower stalk, and root of t in vitro-grown plantlets. Petioles were found
to be the best material for callus induction. Calli induced on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic
acid (4.5 μM) and kinetin (0.46 μM) were conditioned for two weeks on the same medium. These calli differentiated into adventitious
shoots when cultured on 1/2MS basal medium plus kinetin 4.7 μM and silver thiosulphate 10 μM. An addition of GA3 (2.9 μM) and BA (4.4 μM) to MS basal medium, however, induced high frequency t in vitro flowering (86.1%) and multiple shoot
budding which affected the normal complete development of plantlets. Plantlets with a well-developed root system were obtained
six weeks after regenerated shoots had been transplanted to 1/2 MS20 medium containing IBA 1.2 μM. Nuclear DNA content was
measured to check the stability of their ploidy level. Based on DNA flow cytometric analysis, all the regenerants were typically
diploids as the mother plants were, indicating that nuclear DNA content remained stable during cell differentiation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Yu-Ji Lian Guang-Zhe Lin Xiao-Mei Zhao Hak-Tae Lim 《In vitro cellular & developmental biology. Plant》2011,47(2):289-296
Inter-specific somatic hybrids of leaf mustard (Brassica juncea) and broccoli (Brassica oleracea) were established to introduce cytoplasmic male sterility (CMS) and Verticillium dahliae Kleb. resistance from broccoli to leaf mustard. Protoplasts isolated from hypocotyls and cotyledons of inbred lines of leaf
mustard and broccoli were fused using 40% (w/v) polyethelene glycol and then cultured in modified k8p medium supplemented with 0.2 mg/l 2,4-dichlorophenoxi-acetic acid,
0.5 mg/l 6-benzyladenine (BA), 0.1 mg/l naphthaleneacetic acid (NAA), and 0.1 mg/l kinetin (Kin), and 0.4 M mannitol as osmoticum.
At the eight- to ten-cell stage, divided cells were transferred to Kao’s basal medium supplemented with 0.3 M sucrose as carbon
source and 0.1% agarose, 2 mg/l BA, 2 mg/l zeatin (ZEA), 1 mg/l NAA, and 0.5 mg/l Kin for callus proliferation. After 35 d,
when small calli reached 2–3 mm in diameter, calli were transferred to regeneration medium containing 5 mg/l ZEA and 2 mg/l
indole-3-acetic acid. The chromosome numbers of putative somatic hybrids varied from 46 to 54. A total of ten plants showed
a 0.5-kb, CMS-specific band, while two regenerated plants showed a missing band similar to that of leaf mustard by polymerase
chain reaction amplification using Ogura CMS-specific primers. Hybrid state was confirmed by random amplified polymorphic
DNA analysis. Regenerated plants had normal petals and stamens, but only two plants produced pollen and set seed. 相似文献
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Antimicrobial activity studies on a trypsin-chymotrypsin protease inhibitor obtained from potato 总被引:5,自引:0,他引:5
Kim JY Park SC Kim MH Lim HT Park Y Hahm KS 《Biochemical and biophysical research communications》2005,330(3):921-927
A 5.6 kDa trypsin-chymotrypsin protease inhibitor was isolated from the tubers of the potato (Solanum tuberosum L cv. Gogu) by extraction of the water-soluble fraction, dialysis, ultrafiltration, and C18 reversed-phase high performance liquid chromatography. This inhibitor, which we named potamin-1 (PT-1), was thermostable and possessed antimicrobial activity but lacked hemolytic activity. PT-1 strongly inhibited pathogenic microbial strains, including Candida albicans, Rhizoctonia solani, and Clavibacter michiganense subsp. michiganinse. Automated Edman degradation showed that the N-terminal sequence of PT-1 was NH2-DICTCCAGTKGCNTTSANGAFICEGQSDPKKPKACPLNCDPHIAYA-. The sequence had 62% homology with a serine protease inhibitor belonging to the Kunitz family, and the peptide inhibited chymotrypsin, trypsin, and papain. This protease inhibitor, PT-1, was composed of polypeptide chains joined by disulfide bridge(s). Reduced PT-1 almost completely lost its activity against fungi and proteases indicating that disulfide bridge is essential for its protease inhibitory and antifungal activity. These results suggest that PT-1 is an excellent candidate as a lead compound for the development of novel oral or other anti-infective agents. 相似文献
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