1.Determination of marker compounds in plants of Rhodiola L. from different habitats by RP-HPLC
Yundong SHAO ; Yanfang SU ; Hongjian YU ; Fuming LI
Chinese Traditional and Herbal Drugs 1994;0(05):-
ObjectTo develop the reliable RP-HPLC methods for the determination of salidroside, tyrosol, rosavin, rosin, and rosarin in the plants of Rhodiola L. and to evaluate their species from different habitats. Methods Method Ⅰ: methanol-water (0.5 mmol/L SDS in 1% acetic acid aqueous solution) system for the analysis of salidroside; method Ⅱ: acetonitrile-water system for rosavin; method Ⅲ: aqueous acetonitrile-phosphoric gradient system for salidroside, tyrosol, rosavin, rosin, and rosarin. Results The contents of salidroside in different species range from 0.021% to 1.420%, and those of rosavin in all species are very limited or undetected except in Rhodiola rosea L. and R. sachalinensis. The contents of the five marker ingredients are significantly species- and habitat-dependent. Conclusion Three RP-HPLC methods are established for quantitative analysis of the above five marker ingredients in the meantime, respectively. Evaluation of the quality of varied species of Rhodiola L. shows that R. rosea growing in Xinjiang Uygur Autonomous Region and R. sachalinensis growing in Jilin province are the two better species contained with abundant above-mentioned ingredients in China.
3.Structure prediction and biological activity analysis of dybowskin-1ST antimicrobial peptide in Rana dybowskii.
Yue LIU ; Xuechao SHAO ; Tiantian WANG ; Xinying WANG ; Nan LI ; Yundong ZHAO ; Wei XIA ; Liyuan SUN
Chinese Journal of Biotechnology 2021;37(8):2890-2902
The evolution, structure and antigenic epitopes prediction of Rana dybowskii antimicrobial peptide dybowskin-1ST were carried out using bioinformatics software available online. Its antibacterial mechanism and structural properties were analyzed, and its activity was verified by applying wound healing assay in mice and bacteriostatic assay in vitro. This provides the theoretical basis for the improvement of parental peptide and the development of novel derivative peptides. The software MEGA_X were used to conduct homology alignment and to construct a phylogenetic tree. The online software ProtParam, ProtScale, PeptideCutter, signal, TMHMM Server were respectively used to predict the physicochemical parameters, hydrophilia/hydrophobicity, shear sites, signal peptides, and transmembrane domains of dybowskin-1ST. The online software SOPMA, Jpred4, DNAstar Protean were used to predict the secondary structure of dybowskin-1ST, and SWISS-MODEL, I-TASSER were used to predict the tertiary structure. ABCpred and SYFPEITHI were respectively used to predict its B-and T-cell epitopes. The effect of dybowskin-1ST on the wound healing was observed on experimental mice. Kirby-Bauer method and dilution method were used to determine the bacteriostatic activity of dybowskin-1ST. The dybowskin-1ST consists of 59 amino acid residues, of which leucine accounts for 16.9%, with a molecular formula of C₃₁₈H₅₁₀N₈₀O₉₃S₂. Its theoretical isoelectric point is 5.10 and the charge is -2. The dybowskin-1ST and dybowskin-1CDYa are closely related phylogenetically. The secondary structure of dybowskin-1ST predicted by the three methods were similar, which consisted of α-helix (44.07%), extended strand (16.95%), β-turns (3.39%), and random coil (35.39%). The prediction of tertiary structure showed that dybowskin-1ST was mainly composed of α-helix, and it was regarded as a hydrophilic protein with signal peptide sequence. Subcellular localization analysis showed that the probability of secreting the mitochondrial targeted peptides was 0.944. Dybowskin-1ST is an extracellular protein with no transmembrane structure region, but contains seven phosphorylation sites, three T-cell epitopes and eight B-cell epitopes. The dybowskin-1ST promoted wound healing and effectively inhibited the growth of Escherichia coli and Staphylococcus aureus. However, it had limited antibacterial activity against fungi and drug-resistant bacteria. Although the structure of dybowskin-1ST is rich in α-helix, the verification experiments showed that its antibacterial ability needs to be enhanced. The reason may be that it is a negatively charged and hydrophilic protein, and amino acid modification with the aim of increasing the number of positive charges and changing the hydrophobicity may be used to obtain derived peptides with enhanced activity.
Amino Acid Sequence
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Animals
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Mice
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Phylogeny
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Pore Forming Cytotoxic Proteins
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Protein Structure, Secondary
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Ranidae