Journal: Scientific Reports

Article Title: Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

doi: 10.1038/s41598-021-01543-5

Figure Lengend Snippet: Experimental setup and optical properties. ( a ) Optical setup of the tunable pulse laser inactivation system. ( b ) Optical absorbance ratio (α cv /α 0 ) between stained (α cv ) and unstained (α 0 ) E. coli O1 solutions. The inset shows the optical absorption spectrum (absorbance) of unstained E. coli solution (brown line) and a crystal violet dye-stained E. coli solution (blue line). ( c ) Relative ratio of scattering intensity as a function of pulse laser wavelength for E. coli O1. Here, we normalize the scattering intensity of both stained (σ cv ) and unstained (σ 0 ) E. coli O1 to 1 at 650 nm.

Article Snippet: The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α.

Techniques: Staining

Journal: Scientific Reports

Article Title: Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

doi: 10.1038/s41598-021-01543-5

Figure Lengend Snippet: The results of the efficacy of inactivation for unstained E. coli O1 by using the tunable pulsed laser. ( a ) Control plate of a 420 nm pulsed laser, ( b ) plate inactivated by a 420 nm pulsed laser, and ( c ) the number of CFU on the control plate (1235 ± 61 CFU) and treated plate (0.33 ± 0.1 CFU) with a 420 nm pulsed laser. ( d ) Control plate of a 500 nm laser, ( e ) plate inactivated by a 500 nm laser, and ( f ) the number of CFU on the control plate (2211 ± 164 CFU) and plate (659 ± 97 CFU) treated with a 500 nm pulsed laser. ( g ) Control plate of a 600 nm laser, ( h ) inactivated plate by a 600 nm laser, and ( i ) the number of CFU on the control plate (4974 ± 953 CFU) and plate (5873 ± 930 CFU) treated with a 600 nm pulsed laser. ( j ) Control plate of a 650 nm laser, ( k ) inactivated plate by a 650 nm laser, and ( l ) the number of CFU on the control plate (3852 ± 986 CFU) and treated plate (4827 ± 383 CFU) with a 650 nm pulsed laser.

Article Snippet: The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α.

Techniques: Control

Journal: Scientific Reports

Article Title: Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

doi: 10.1038/s41598-021-01543-5

Figure Lengend Snippet: Dose (D) response of stained or unstained E. coli inactivated by tunable pulsed laser treatment. The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α. The dose-based inactivation rate constants Γ (cm 2 /kJ) of stained samples (solid lines of b , d , f ) were theoretically obtained based on those of unstained results (solid lines of a , c , e ). The experimentally ( a , c , e ) and theoretically ( b , d , f ) determined values of Γ (cm 2 /kJ) are described in Table .

Article Snippet: The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α.

Techniques: Staining

Journal: Scientific Reports

Article Title: Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

doi: 10.1038/s41598-021-01543-5

Figure Lengend Snippet: The results of the efficacy of inactivation for crystal violet-stained E. coli O1 by using the tunable pulsed laser. ( a ) Control plate of a 420 nm pulsed laser, ( b ) plate inactivated by a 420 nm pulsed laser, and ( c ) the number of CFU on the control plate (995 ± 70 CFU) and treated plate (4.3 ± 0.9 CFU) with a 420 nm pulsed laser. ( d ) Control plate of a 500 nm laser, ( e ) inactivated plate by a 500 nm laser, and ( f ) the number of CFU on the control plate (1457 ± 175 CFU) and treated plate (48 ± 8.5 CFU) with a 500 nm pulsed laser. ( g ) Control plate of a 600 nm laser, ( h ) plate inactivated by a 600 nm laser, and ( i ) the number of CFU on the control plate (776 ± 50.0 CFU) and treated plate (197 ± 6.0 CFU) with a 600 nm pulsed laser. ( j ) Control plate of a 650 nm laser, ( k ) plate inactivated by a 650 nm laser, and ( l ) the number of CFU on the control plate (3034 ± 601 CFU) and plate (1276 ± 158 CFU) treated with a 650 nm pulsed laser.

Article Snippet: The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α.

Techniques: Staining, Control

Journal: Scientific Reports

Article Title: Mechanism of transient photothermal inactivation of bacteria using a wavelength-tunable nanosecond pulsed laser

doi: 10.1038/s41598-021-01543-5

Figure Lengend Snippet: Living or dead states of E. coli determined from Live/Dead assay with fluorescence microscopy measurements (10 μm scale bar). ( a ) Green and red, and ( b ) only red fluorescence images before pulsed laser irradiation, and ( c ) green and red, and ( d ) only red fluorescence images after pulsed laser irradiation (420 nm and 180 kJ/cm 2 ). ( e ) Green and red, and ( f ) only red fluorescence images before DUV irradiation, and ( g ) green and red, and ( h ) only red fluorescence images after DUV irradiation (λ = 265 nm and doseage = 60 mJ/cm 2 ). Images ( a ), ( c ), ( e ), and ( g ) show fluorescence emitted from both thiazole orange and propidium iodide and images ( b ), ( d ), ( f ), and ( h ) show fluorescence emitted from only propidium iodide. Photographs of CFU-evaluations ( i ) before and ( j ) after DUV irradiation are shown to compare with the fluorescence images ( e – h ).

Article Snippet: The blue circles are the inactivation rates with 420 nm treatments, the green circles are the inactivation rates with 500 nm treatments, the orange circles are the inactivation rates with 600 nm treatments, and the red circles are the inactivation rates with 650 nm treatments. ( a ) Dose response of unstained E. coli O1, ( b ) dose response of crystal violet-stained E. coli O1, ( c ) dose response of unstained E. coli ATCC 8739, ( d ) dose response of crystal violet-stained E. coli ATCC 8739, ( e ) dose response of unstained E. coli DH5α, and ( f ) dose response of crystal violet-stained E. coli DH5α.

Techniques: Live Dead Assay, Fluorescence, Microscopy, Irradiation

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: UMI-guided single locus sequence typing method for phylotyping Cutibacterium acnes from skin samples

doi: 10.3389/fcimb.2026.1807759

Figure Lengend Snippet: Performance of the SLST assay on spike-in mixtures of C. acnes DNA with increasing background DNA. (A) Total number of full-length SLST sequences reconstructed from spike-in mixtures containing decreasing proportions of C. acnes genomic DNA (SpikeMix-50, -10, -5, and -0.5) supplemented with E. coli DNA. Bars represent mean counts across replicates (± SD), and dots indicate individual replicates. (B) Relative abundances of SLST types recovered from the same spike-in mixtures, shown alongside the theoretical composition (Expected, left). Stacked bars illustrate the five targeted SLST types (A1, G1, H2, K2, L1), with residual reads grouped as “Others (< 1%)” and “Unassigned.” All SpikeMix samples were processed without pre-amplification, using 2 µL of purified DNA at 0.125 ng/µL (total input 0.25 ng) directly into the molecular barcoding step, yielding absolute C. acnes DNA inputs of 125 pg (SpikeMix-50), 25 pg (SpikeMix-10), 12.5 pg (SpikeMix-5), and 1.25 pg (SpikeMix-0.5).

Article Snippet: This community was supplemented with Escherichia coli genomic DNA (ATCC 8739D-5) to progressively reduce the fraction of C. acnes DNA.

Techniques: Amplification, Purification