Related Experiment Video
Updated: Jan 25, 2026
Antigen-Capture Enzyme-Linked Immunosorbent Assay for Specific Detection of Mycoplasma pneumoniae
Published on: February 24, 2023
Intraspecies Gene Variation within Putative Epitopes of Immunodominant Protein P48 of Mycoplasma agalactiae
P Panahi1, S A Pourbakhsh1,1, T Zahraei Salehi2
1Mycoplasma Reference Laboratory, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.
Abstract:
P48 protein of Mycoplasma agalactiae is used to diagnose infection and was identified as potential vaccine candidate. According to the genetic nature of mycoplasma and variable sensitivity in P48-based serological diagnosis tests, intra species variation of P48 nucleotide sequence investigated in 13 field isolates of difference province of Iran along with three vaccine strains. Samples were collected from sheep and goat and were cultured in modified PPLO broth. Two pair of primer employed to confirm genus and species of isolates and a pair of primer has developed to amplify the P48 gene. The sequencing results of PCR products were aligned and analyzed besides published sequences in GenBank. T-Cell and B-Cell epitopes and antigenicity of sequence were computationally predicted. The results have shown P48 nucleotide sequences are 99.9% identical in field isolates and vaccine strain of Iran, but analysis of GenBank published sequences have shown divergence up to 5.3% at the nucleotide level and up to 4.9% divergence in protein level of P48 sequences of Iran isolates and other available sequences in GenBank. Single nucleotide polymorphism exists in 89 positions and variable amino acid was observed at 25 residues. Phylogenetic analyses have shown that Mycoplasma agalactiae isolates fall into three main groups based on P48 nucleotide sequences. Immunoinformatics analysis of all available P48 nucleotide sequences have revealed that gene variation lead to differences in immunological properties, but the gene in Iranian isolates are conservative and stable. The sequence variation in epitopes can be underlying source of antigen heterogeneity as a result, affect serological tests accuracy. Due to the high level of divergence in worldwide isolates and high degree of similarity in P48 protein of Iranian isolates, designing recombinant P48 protein based on local pattern can increase the sensitivity and consistency of serological test.
Insights
Mycoplasma agalactiae P48 gene sequences in Iranian isolates show high similarity, unlike global strains. This genetic stability in local P48 protein can improve diagnostic test accuracy and vaccine development.
Area of Science:
- Veterinary Microbiology
- Molecular Epidemiology
- Immunoinformatics
Background:
- The P48 protein of Mycoplasma agalactiae is crucial for diagnosing infections and serves as a potential vaccine candidate.
- Variability in P48 nucleotide sequences can affect the sensitivity and accuracy of serological diagnostic tests.
Purpose of the Study:
- To investigate the intra-species variation of the P48 nucleotide sequence in Mycoplasma agalactiae field isolates from Iran.
- To compare Iranian P48 sequences with global strains and predict immunological properties.
Main Methods:
- Nucleotide sequencing of the P48 gene from 13 field isolates and 3 vaccine strains.
- Bioinformatic analysis including sequence alignment, phylogenetic analysis, and epitope prediction.
- Computational prediction of T-cell and B-cell epitopes and antigenicity.
Main Results:
- P48 nucleotide sequences from Iranian isolates exhibited 99.9% identity, indicating high conservation.
- Global P48 sequences showed up to 5.3% nucleotide divergence and 4.9% protein divergence compared to Iranian isolates.
- Phylogenetic analysis revealed three distinct groups of Mycoplasma agalactiae based on P48 sequences.
- Sequence variations, particularly in epitopes, can lead to antigen heterogeneity and impact diagnostic accuracy.
Conclusions:
- Mycoplasma agalactiae P48 gene is highly conserved within Iranian isolates but shows significant divergence globally.
- The stability of the P48 protein in Iranian isolates suggests potential for developing sensitive and consistent serological diagnostic tests.
- Designing recombinant P48 protein based on local Iranian strains could enhance diagnostic test performance.
Related Concept Videos
02:11Proteins: From Genes to Degradation
Transcription is the synthesis of RNA...
02:11Proteins: From Genes to Degradation
01:14What is Variation?
The range, standard deviation, standard error, and variance are the different measures of variation.
Range: The range is the difference between its maximum and...
02:53Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
01:19Variation
When independent and dependent variables are plotted on a scatter plot, the slope of a line is a value that describes the rate of change between the two...
01:18Variation of Atmospheric Pressure
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...