Microbiological strain identification

Service introduction

         Ribonucleic acid (rRNA) is the most abundant RNA in cells, accounting for more than 80% of the total RNA. It is composed of highly conserved and variable regions.

        The rRNA of bacteria includes 5S, 16S, and 23S. 5S rRNA has little information and is not suitable for analysis. 23S rRNA is large and has a lot of information, but the mutation rate of bases is relatively fast, and it is not suitable for bacterial identification either. 16S rDNA is the DNA sequence of the 16S rRNA that encodes the small subunit of the ribosome of prokaryotes. It is relatively stable genetically, with a length of around 1550±200 bp, and has a moderate amount of information, which can be used to study systematic evolution. More than 10,000 species of bacterial 16S rDNA have been reported. 16S sequencing is the gold standard for bacterial strain identification.

Technical procedures

16s rDNA schematic diagram

Sample requirements and notes

• Genomic DNA: OD 260/280 is between 1.8-2.0 (OD260/230 is preferably greater than 1.5), concentration ≥ 30 ng/μl, volume ≥ 20 μl, and no obvious degradation.

  
  

• It is recommended to provide cultured bacterial liquid, with a volume >2 ml. Please ensure that the provided bacterial liquid is a single colony that has been isolated and cultured. The full experimental fee will be charged for sequencing double peaks caused by sample impurities.

  
  

• For special samples, such as actinomycetes and anaerobic bacteria, please provide genomic DNA directly. For Gram-positive bacteria, it is recommended to provide genomic DNA.

  
  

• We do not accept pathogenic samples. If the bacteria are pathogenic, please provide genomic DNA and heat treatment to kill the pathogenic bacteria.

  
  

• Since some fungi are similar in morphology to bacteria and are difficult to distinguish, it is recommended to consider analyzing the ITS region of fungi when 16S rDNA results cannot be obtained.

  
  

• For samples with double peaks, cloning sequencing services can be provided

  
  

Results delivery

• Sequence file and sequencing peak chart

  
  

• 16S rDNA sequence splicing file

  
  

• Sequence analysis and comparison results

  
  

Additional services

        For samples with double peaks, cloning sequencing services can be provided, priced at 380 yuan/sample. It includes: fragment cloning, sequencing of 6 positive clones, and sequence comparison analysis.

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Bacillus 16SrDNA strain identification service entrustment letter