Raman spectroscopy revealsM. tuberculosisstrains with different antibiotic susceptibility

Abstract

The drug resistance of Mycobacterium tuberculosis (MbT) remains a serious challenge to global public health as extensively drug resistant tuberculosis usually leads to a lethal outcome. In the case of diseases with resistant strains, it is extremely important to identify a specific strain as soon as possible in order to start an adequate therapy. One such diagnostic method could be the Raman spectroscopy method. We investigated M. tuberculosis strains of the Beijing family deactivated by heating, with different drug sensitivity: sensitive, multi- and extensively drug resistant. Samples, obtained from patient specimens were investigated by Raman spectrometry with the He–Ne (632.8 nm) laser excitation source. As a result, a set of optimal experimental parameters for strain discrimination were determined based on the cell-wall spectral differences. These differences distinguish between drug-sensitive and drug-resistant strains as well as between strains isolated from material samples taken from patients suffering from pulmonary and extra-pulmonary forms of tuberculosis. We suggest that the obtained results allow the usage of the Raman spectroscopy as a fast diagnostic tool for determining various strains in clinical medical practice.

Raman spectroscopy for glutathione measurements in Mycobacterium tuberculosis strains with different antibiotic resistance

“…Sequential analysis of the main components of the cell wall, such as proteins and lipids, are performed in “fingerprint” 600–1800 cm −1 region. [ 21 ] We have selected the region 1000–1500 cm −1 for GSH analysis. KnowItAll Vibrational Spectroscopy Edition (BioRad, USA) software was used to perform baseline correction and normalization to the highest peak intensity for all selected spectra and further analysis of the peaks positions and their intensity.…”

“…The detailed experimental procedure was described in previous studies. [21,22] The collection of MbT strains consists of strains isolated in the Saint-Petersburg State Research Institute of Phthisiopulmonology. [21,22] For our investigation, we have used strains with different drugs sensitivity obtained from clinical material (sputum and bones for extra-pulmonary strains).…”

“…[21,22] The collection of MbT strains consists of strains isolated in the Saint-Petersburg State Research Institute of Phthisiopulmonology. [21,22] For our investigation, we have used strains with different drugs sensitivity obtained from clinical material (sputum and bones for extra-pulmonary strains). Characteristics of the strains are shown in Table 1, where medium drugresistant (MDR) and extreme drug-resistant (XDR) strains are defined according to WHO classification.…”

“…One of the promising candidate for such possible markers is GSH revealed in the previous work. [ 21 ] Thus, in this study, we perform detailed analysis of GSH content in MbT with various drug resistance.…”

“…Also, the identification of the drug resistance markers that can correlate with bacterial cell death and resistance mechanisms remains a challenge. In our previous investigations, [21,22] we have performed a Raman "screening" for clinical MbT with different drug resistance. One of the promising candidate for such possible markers is GSH revealed in the previous work.…”