Journal: Microbiology Spectrum

Article Title: VLX600, an anticancer iron chelator, exerts antimicrobial effects on Mycobacterium abscessus infections

doi: 10.1128/spectrum.00719-25

Figure Lengend Snippet: Antimycobacterial efficacy of VLX600 against type strains of M. abscessus . ( A ) The MICs of VLX600 against type strains of M. abscessus were determined with a broth microdilution assay. Each strain of M. abscessus was diluted in CAMHB to McFarland standard 0.5 and further diluted 1:100 in CAMHB. VLX600 was serially diluted in CAMHB and applied to M. abscessus cultures in 96-well plates ( n = 3). The plates were then cultured at 37°C for 1 week, and the OD 600 was measured to determine the MIC. The MIC was defined as the lowest concentration of VLX600 that inhibited bacterial growth by at least 90%. The MICs are shown as red dots on the graphs. ( B ) The antimycobacterial efficacy of VLX600 against M. abscessus was evaluated with a CFU assay in the direct treatment model. The type strain of M. abscessus subsp. abscessus (ATCC 19977) culture from the broth microdilution assay was serially diluted in phosphate-buffered saline (PBS) and spread on 7H10 agar plates. The plates were incubated at 37°C until colonies appeared. Asterisks above the bars indicate statistical significance compared to the vehicle. ( C ). The antimycobacterial efficacy of VLX600 in the J774A.1 infection model was evaluated with a CFU assay. J774A.1 cells were infected with the type strain of M. abscessus subsp. abscessus (ATCC 19977) at an MOI of 10, followed by treatment with different doses of VLX600 ( n = 3). The plates were then cultured at 37°C for 48 h. The intracellular bacteria were harvested by lysing the cells with 1% Triton X-100, and then samples were spread on 7H10 agar plates for the CFU assay. The statistical significance was determined by one-way analysis of variance with Tukey’s multiple comparison test, and the results are denoted as follows: * P < 0.05, ** P < 0.01, and *** P < 0.001. The error bars represent the standard errors of the means.

Article Snippet: Type strains of M. avium , M. intracellulare subsp. yongonense , M. paraintracellulare , M. gordonae , M. paragordonae , M. marinum , M. vaccae , M. terrae , M. chleonae subsp. bovistauri , M. chelonae subsp. gwanakae (ATCC 25291, 05-1390 T , MOTT64, ATCC14470, 49061 T , ATCC927, ATCC15483, ATCC15755, QIA-37, and MOTT36W, respectively), and the M. bovis BCG strain Tokyo were used in this study All mycobacteria were cultured in complete 7H9 broth supplemented with 10% albumin-dextrose-catalase (ADC), 2.5% glycerol, and 0.2% Tween-80 until they reached the stationary phase in a shaking incubator at 37°C except for M. marinum , M. gordonae , and M. paragordonae , which were grown at 30°C.

Techniques: Microdilution Assay, Cell Culture, Concentration Assay, Colony-forming Unit Assay, Saline, Incubation, Infection, Bacteria, Comparison

Journal: Microbiology Spectrum

Article Title: VLX600, an anticancer iron chelator, exerts antimicrobial effects on Mycobacterium abscessus infections

doi: 10.1128/spectrum.00719-25

Figure Lengend Snippet: Abrogation of the antimycobacterial activity of VLX600 by the addition of iron. The antimycobacterial activity of VLX600 (16 µg/mL) against the type strain of M. abscessus subsp. abscessus (ATCC 19977) was evaluated in the presence of various metal ions. The cultures were incubated at 37°C, and the CFUs were measured daily ( n = 3). The antimycobacterial activity of VLX600 was only abrogated by the addition of Fe 2+ and Fe 3+ in a dose-dependent manner, whereas the addition of other metal ions did not affect its activity except for Cu + . The statistical significance was determined by two-way analysis of variance with Tukey’s multiple comparison test, and the results are denoted as follows: * P < 0.05, ** P < 0.01, and *** P < 0.001. The error bars represent the standard errors of the means.

Article Snippet: Type strains of M. avium , M. intracellulare subsp. yongonense , M. paraintracellulare , M. gordonae , M. paragordonae , M. marinum , M. vaccae , M. terrae , M. chleonae subsp. bovistauri , M. chelonae subsp. gwanakae (ATCC 25291, 05-1390 T , MOTT64, ATCC14470, 49061 T , ATCC927, ATCC15483, ATCC15755, QIA-37, and MOTT36W, respectively), and the M. bovis BCG strain Tokyo were used in this study All mycobacteria were cultured in complete 7H9 broth supplemented with 10% albumin-dextrose-catalase (ADC), 2.5% glycerol, and 0.2% Tween-80 until they reached the stationary phase in a shaking incubator at 37°C except for M. marinum , M. gordonae , and M. paragordonae , which were grown at 30°C.

Techniques: Activity Assay, Incubation, Comparison