Fluorescence change of Fusobacterium nucleatum due to Porphyromonas gingivalis

Abstract

The aim of this study was to measure changes in the fluorescence of Fusobacterium nucleatum interacting with Porphyromonas gingivalis for excitation with blue light at 405-nm. P. gingivalis was mono- and co-cultivated in close proximity with F. nucleatum. The fluorescence of the bacterial colonies was photographed using a QLF-D (Quantitative Light-induced Fluorescence-Digital) Biluminator camera system with a 405 nm light source and a specific filter. The red, green and blue intensities of fluorescence images were analyzed using the image analysis software. A fluorescence spectrometer was used to detect porphyrin synthesized by each bacterium. F. nucleatum, which emitted green fluorescence in single cultures, showed intense red fluorescence when it was grown in close proximity with P. gingivalis. F. nucleatum co-cultivated with P. gingivalis showed the same pattern of fluorescence peaks as for protoporphyrin IX in the red part of the spectrum. We conclude that the green fluorescence of F. nucleatum can change to red fluorescence in the presence of adjacent co-cultured with P. gingivalis, indicating that the fluorescence character of each bacterium might depend on the presence of other bacteria.

Autofluorescence Detection Method for Dental Plaque Bacteria Detection and Classification: Example of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Streptococcus mutans

“…Indeed, the interaction between different oral bacteria is likely to change the fluorescent profile. However, the fluorescent spectrum in a dual-species biofilm could still reflect the presence of PG [ 33 ]. While uncertainty remains in the case of multi-species biofilms, the ability of fluorescent spectra in bacterial differentiation needs to study further using multi-species biofilms or freshly collected dental plaque combined with microbiome analyses.…”

Red/Orange Autofluorescence in Selected Candida Strains Exposed to 405 nm Laser Light

“…Furthermore, it has been observed that the autofluorescence of individual bacterial strains can change when multiple strains coexist within a biofilm. For instance, the coexistence of Fusobacterium nucleatum with Porphyromonas gingivalis can lead to alterations in autofluorescence characteristics [ 45 ]. Similarly, Porphyromonas micros has been reported to exhibit red fluorescence in the proximity of Porphyromonas gingivalis [ 45 ].…”

“…For instance, the coexistence of Fusobacterium nucleatum with Porphyromonas gingivalis can lead to alterations in autofluorescence characteristics [ 45 ]. Similarly, Porphyromonas micros has been reported to exhibit red fluorescence in the proximity of Porphyromonas gingivalis [ 45 ]. These observations lend support to the quorum sensing (QS) theory within a biofilm.…”

“…The capability for variable autofluorescence among microorganisms is primarily attributed to the differential quantities of the porphyrins present within their cells, which can influence the distinct luminescence observed [ 45 ]. Porphyrins are synthesized by microorganisms as part of their biosynthetic processes [ 44 ].…”

Spatiotemporal monitoring demonstrates prebiotic treatment responses in a periodontal multispecies biofilm model

“…Green fluorescence of F. nucleatum has been reported a few times under the excitation by visible blue light [48,49], but the origin of fluorescence has never been addressed. Some studies also point to the dependency of its fluorescence on available nutrients and interactions with adjacent bacteria [50,51]. The dependency on growth conditions and the lack of knowledge about the fluorescent component make it challenging to get disclosure on whether all present cells are fluorescent in the green channel.…”