A kind of recombinant bacteria expressing sef14 functional pili and its application

A technology of recombinant strains and expression vectors, which is applied in the fields of biomedicine and immunodiagnosis, and can solve the problems of lack of specific targeting

Active Publication Date: 2022-01-28
YANGZHOU UNIV
View PDF0 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] At present, the infection situation of Salmonella Enteritidis in chicken flocks is serious, which has brought a severe test to human food safety, but there is currently a lack of specific targeted detection and monitoring technology for Salmonella Enteritidis infection in chicken flocks to purify it

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • A kind of recombinant bacteria expressing sef14 functional pili and its application
  • A kind of recombinant bacteria expressing sef14 functional pili and its application
  • A kind of recombinant bacteria expressing sef14 functional pili and its application

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0041] Amplification and cloning of embodiment 1 Salmonella enteritidis sef14 operon

[0042] Using the genome of Salmonella enteritidis standard strain C7920 as a template, use P505 ultra-fidelity enzyme (purchased from Nanjing Novizan Biotechnology Co., Ltd.) to amplify the sef14 operon gene fragment, and its coding sequence without signal peptide is:

[0043]

[0044]

[0045]

[0046]

[0047] The upstream and downstream primers for amplifying the sequence are:

[0048] sef-up: 5'-G GCAT GC AAAATg gCg TgAgTATAT TAg CAT CCg CA-3';

[0049] set-lo: 5'-C G TCG AC TT ATT ATAATT CAA TTT CTG TCG CAT AT-3'.

[0050] Wherein the underline marks represent SphI and SalI restriction sites respectively, and the amplified product is 4268bp ( figure 1 ).

[0051] The sef14 operon gene fragment amplified by PCR and the pBR322 vector were digested with SphI and SalI, and then circularized in vitro by DNA ligase. The product was named pBR-sef14, and then transformed int...

Embodiment 2

[0052] Expression and identification of embodiment 2SEF14 pili and SefA recombinant protein

[0053] Expression of SEF14 pili: pBR-sef14 was transformed into Escherichia coli SE5000, cultured at 37°C for 12 hours, and pili were extracted by heat extraction method. SE5000 containing only pBR322 empty vector was used as negative control. The steps of the heat extraction method are: place the above bacterial solution at 4°C and centrifuge at 4500rpm for 10 minutes, discard the supernatant and wash twice with sterile PBS; then add 1M NaCl-0.05M Tris-HCl (pH=7.4) solution to resuspend the bacterial cells and Place in a water bath at 62°C for 30 minutes; centrifuge at 8,000 rpm for 20 minutes, transfer the supernatant to a new centrifuge tube for volume measurement, slowly add saturated ammonium sulfate dropwise to a final concentration of 25%, and precipitate overnight; centrifuge at 14,000 rpm for 30 minutes the next day, discard the supernatant, and use Resuspend the pellet in st...

Embodiment 3

[0060] Example 3 Indirect agglutination test of recombinant bacteria based on SEF14 pili to detect Salmonella Enteritidis infection in chicken flocks

[0061] After cultivating the recombinant bacteria expressing SEF14 pili obtained in Example 1-3 for 12 hours, the amount of bacteria was adjusted to be 5×10 9CFU / mL, then centrifuge at 4000rpm for 5min, discard the supernatant and wash twice with sterile PBS. Use PBS containing 0.25% formaldehyde to resuspend the bacteria and place it overnight at 4°C as the agglutinating antigen. The above-mentioned agglutinated antigen was respectively mixed with 10 parts of SPF chicken infection Salmonella enteritidis serum (numbering is 1-10), 30 parts of clinical Salmonella enteritidis positive serum (numbering is 11-40), 10 parts of clinical Salmonella pullorum serum (numbering is 41-50) ), 10 clinical Salmonella typhi positive chicken serum (number 51-60), 10 clinical E. coli positive chicken serum (number 61-70), 10 SPF chicken infecti...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a recombinant plasmid, which is the sef14 The operon gene is inserted into the expression vector pBR322. The invention also discloses a recombinant bacterial strain, which is obtained by introducing the recombinant plasmid into the inert carrier strain S9. The invention also discloses the preparation method and application of the recombinant bacterial strain. In the present invention, for the first time, SEF14 is displayed on the surface of an inert carrier strain S9 to express a single pili SEF14, which can avoid background non-specific reactions and at the same time specifically detect Salmonella Enteritidis infection, and has the advantages of rapidity, specificity, sensitivity, simplicity and low price. , while meeting the requirements of on-site and large-scale testing. The SEF14 functional pili of the present invention can be used to detect and monitor Salmonella Enteritidis infected chicken flocks after displaying and expressing a single pili SEF14 on the surface of an inert carrier. Plate agglutination reaction, by visually observing the reaction results on site and accurately judging whether the animal is infected by Salmonella Enteritidis.

Description

technical field [0001] The invention belongs to the technical field of biomedicine and immunodiagnosis, and specifically relates to a recombinant bacterium expressing SEF14 functional pili and its application. Background technique [0002] Salmonella enteritidis has no host specificity, is one of the main pathogenic bacteria that cause food poisoning in humans, and can cause non-typhoid gastroenteritis in humans, livestock and poultry. About 93.8 million people in the world are infected with Salmonella every year, and 155,000 people die; and in my country, Salmonella gastroenteritis caused by Salmonella accounts for about 40% of bacterial food poisoning every year, ranking first in bacterial food poisoning, and Salmonella Enteritidis It is the main cause of Salmonella food poisoning outbreaks. [0003] Livestock and poultry products are the main source of Salmonella Enteritidis infection, among which eggs are the most common carrier. This is because Salmonella Enteritidis ca...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(China)
IPC IPC(8): C12N15/74C12N15/64C12N15/31C12N1/21C12Q1/10C12R1/42
CPCC07K14/255C12N15/74C12Q1/10
Inventor 朱国强侯千禧顾宣强刘家奇段强德夏芃芃
Owner YANGZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap