Human lactoferrin-like peptide and its application
A technology of lactoferrin and ferritin, which is applied in the field of preparation of human lactoferrin, can solve the problems of low yield, high cost, complicated preparation process, etc.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0021] Example 1: Structural design of human lactoferrin-like peptides
[0022] The human lactoferrin peptide LfcinH is formed by protease digestion of the N-terminal α-helix region 14-31 of human lactoferrin (TKCFQWQRNMRKVRGPPVSCIKR), and a hairpin structure with an amphipathic conformation is formed by an intrachain disulfide bond, and the hydrophobic core is " T-shaped arrangement. Bellamy et al found that bovine lactoferrin peptide LfcinB (FKCRRWQWRMKKLGAPSITCVRR) has antibacterial and bactericidal effects compared with human lactoferrin peptide LfcinH, the former is more than 400 times that of the latter; analysis of its structure found that LfcinB has more positive net charges and more Strong hydrophobic strength, the number of positive charges and the strength of hydrophobicity determine its antibacterial ability, but this characteristic is restrictive. The increase in net charge can only improve its antibacterial activity within a certain range. The same is true for th...
Embodiment 2
[0027] Example 2: Recombinant expression of lactoferrin-like peptide
[0028] The sumo fusion expression system was used for E. coli expression or yeast secretion expression, and the expression plasmids encoding the fusion sumo tag DNA sequence fragments SD1, SD2, SD3, SD4, SD5, SD6, SD7 (SD1, SD2, SD3, SD4, The sequences of SD5, SD6, and SD7 are respectively shown in SEQ ID NO.8-SEQ ID NO.14), heat-shock transformation of E. coli expression bacteria BL21 or electric shock transformation of yeast GS115, resistance screening of positive transformants, respectively with IPTG or methanol High-expression strains were screened for induced expression, and monomeric proteins S1-S7 were obtained after two-step Ni column purification and sumo digestion. S1-S7 fusion sumo gene for recombinant secreted expression such as figure 2 shown.
Embodiment 3
[0029] Embodiment 3: Selective effect on skin epidermal microbial flora
[0030] In this example, human lactoferrin peptide S1 purified in Example 2 and its 6 improved peptides (S2-S7) were used to determine the effect on skin epidermal microbial flora dominant flora Staphylococcus epidermidis (Se ), Propionibacterium acnes (PA) and Pseudomonas (Pse), the minimum inhibitory concentration of the subdominant flora Lactobacillus (La), Staphylococcus aureus (Sa).
[0031] The specific steps are as follows: Dilute the above-mentioned series of bacterial solutions cultivated to the logarithmic growth phase to 2×105~7×105cfu.ml -1 ; Use PBS (sodium phosphate buffer solution, pH 7.0) to prepare human lactoferrin peptide S1 and its 6 improved peptides (S2-S7) as a stock solution of 10 times the highest concentration to be tested, and then perform gradient dilution to obtain a series of Diluted lactoferrin peptide solution; add 2ml of diluted bacterial suspension to the sterilized test...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


