Shenoy Varun, Gunda Rashmika, Noble Cora, Haraguchi Annalisa, Stevenson Steven, Daniel Jaiyanth
Department of Biological Sciences, Purdue University Fort Wayne, Fort Wayne, Indiana, USA.
Department of Chemistry and Biochemistry, Purdue University Fort Wayne, Fort Wayne, Indiana, USA.
Cell Biochem Funct. 2024 Mar;42(2):e3963. doi: 10.1002/cbf.3963.
Mycobacterium tuberculosis and nontuberculous mycobacteria such as Mycobacterium abscessus cause diseases that are becoming increasingly difficult to treat due to emerging antibiotic resistance. The development of new antimicrobial molecules is vital for combating these pathogens. Carbon nanomaterials (CNMs) are a class of carbon-containing nanoparticles with promising antimicrobial effects. Fullertubes (C ) are novel carbon allotropes with a structure unique among CNMs. The effects of fullertubes on any living cell have not been studied. In this study, we demonstrate that pristine fullertube dispersions show antimicrobial effects on Mycobacterium smegmatis and M. abscessus. Using scanning electron microscopy, light microscopy, and molecular probes, we investigated the effects of these CNMs on mycobacterial cell viability, cellular integrity, and biofilm formation. C fullertubes at 1 µM inhibited mycobacterial viability by 97%. Scanning electron microscopy revealed that the cell wall structure of M. smegmatis and M. abscessus was severely damaged within 24 h of exposure to fullertubes. Additionally, exposure to fullertubes nearly abrogated the acid-fast staining property of M. smegmatis. Using SYTO-9 and propidium iodide, we show that exposure to the novel fullertubes compromises the integrity of the mycobacterial cell. We also show that the permeability of the mycobacterial cell wall was increased after exposure to fullertubes from our assays utilizing the molecular probe dichlorofluorescein and ethidium bromide transport. C fullertubes at 0.37 µM and C fullerenes at 0.56 µM inhibited pellicle biofilm formation by 70% and 90%, respectively. This is the first report on the antimycobacterial activities of fullertubes and fullerenes.
结核分枝杆菌和非结核分枝杆菌，如脓肿分枝杆菌，由于新出现的抗生素耐药性，其所引发的疾病正变得越来越难以治疗。开发新的抗菌分子对于对抗这些病原体至关重要。碳纳米材料（CNMs）是一类具有潜在抗菌作用的含碳纳米颗粒。富勒管（C）是新型碳同素异形体，其结构在碳纳米材料中独一无二。富勒管对任何活细胞的影响尚未得到研究。在本研究中，我们证明原始富勒管分散体对耻垢分枝杆菌和脓肿分枝杆菌具有抗菌作用。我们使用扫描电子显微镜、光学显微镜和分子探针，研究了这些碳纳米材料对分枝杆菌细胞活力、细胞完整性和生物膜形成的影响。1μM的C富勒管可使分枝杆菌活力降低97%。扫描电子显微镜显示，在暴露于富勒管24小时内，耻垢分枝杆菌和脓肿分枝杆菌的细胞壁结构受到严重破坏。此外，暴露于富勒管几乎消除了耻垢分枝杆菌的抗酸染色特性。使用SYTO-9和碘化丙啶，我们表明暴露于新型富勒管会损害分枝杆菌细胞的完整性。我们还通过使用分子探针二氯荧光素和溴化乙锭转运的实验表明，暴露于富勒管后分枝杆菌细胞壁的通透性增加。0.37μM的C富勒管和0.56μM的C富勒烯分别抑制菌膜生物膜形成70%和90%。这是关于富勒管和富勒烯抗分枝杆菌活性的首次报道。
