title: Differences in cell wall thickness between resistant and nonresistant strains of Mycobacterium tuberculosis: using transmission electron microscopy.
abstract: The ultrastructure of the cell wall of extensively drug-resistant (XDR), multidrug-resistant (MDR) and susceptible tuberculosis (TB) bacilli was viewed under transmission electron microscopy (TEM). Under the TEM, marked differences were observed in the thickness of their cell wall: 20.2 +/-1.5 and 17.1 +/-1.03 nm for the XDR and MDR TB bacilli, respectively, and 15.6 +/- 1.3 nm for the susceptible isolates (p < 0.05). In MDR bacilli, thickening of the cell wall was observed in the intermediate electron-transparent layer (ETL) and outer electron-opaque layer, whereas in XDR TB cells the basal peptidoglycan layer was denser and almost fused with the ETL. Five to seven percent of XDR TB bacilli had the appearance of the stationary phase with cell wall thickness ranging from 21 to 26 nm (p < 0.001). Information provided in this study is of significant importance in terms of drug selection for effective treatment of resistant strains.
authors: Mycobacteriology Research Centre, National Research Institute of Tuberculosis and Lung Disease (NRITLD), WHO Collaborating Centre, Shahid Beheshti University, Tehran, Iran.
authors: Ali Akbar
authors: AA
authors: Velayati
authors: Parissa
authors: P
authors: Farnia
authors: Tengku Azmi
authors: TA
authors: Ibrahim
authors: Rafiuz Zaman
authors: RZ
authors: Haroun
authors: Ho Oi
authors: HO
authors: Kuan
authors: Jalaledin
authors: J
authors: Ghanavi
authors: Poopak
authors: P
authors: Farnia
authors: Ali Naghee
authors: AN
authors: Kabarei
authors: Payam
authors: P
authors: Tabarsi
authors: Abdul Rahman
authors: AR
authors: Omar
authors: Mohammad
authors: M
authors: Varahram
authors: Mohammad Reza
authors: MR
authors: Masjedi
mesh_terms: D002473:Cell Wall / Q000648:ultrastructure*; D024881:Drug Resistance, Bacterial / Q000502:physiology*; D046529:Microscopy, Electron, Transmission; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000648:ultrastructure*