Visualisation and biovolume quantification in the characterisation of biofilm formation in Mycoplasma fermentans

Abstract

The ability of mycoplasmas to persist on surfaces has been widely acknowledged, despite their fastidious nature. However, the organism’s capability to form a recognisable biofilm structure has been identified more recently. In the current study Mycoplasma fermentans was found to adhere to the glass surface forming highly differentiated biofilm structures. The volumes of biofilm microcolonies were quantified and observed to be greater at late growth stage than those at early growth stage. The channel diameters within biofilms were measured with Scanning Electron Microscopy images and found to be consistent with the size observed in Confocal Laser Scanning Microscope images. The combination of imaging methods with 3D visualisation provides key findings that aid understanding of the mycoplasma biofilm formation and true biofilm architecture. The observations reported here provide better understanding of the persistence of these minimalist pathogens in nature and clinical settings.

Mycoplasmas as Host Pantropic and Specific Pathogens: Clinical Implications, Gene Transfer, Virulence Factors, and Future Perspectives

“…Raymond et al also observed many ultrastructure molecules on the ciliated epithelium of the respiratory tracts in M. hyo infected pigs, they are essential for biofilm formation on abiotic surfaces (Raymond et al, 2018). For the first time, Awadh and coworkers have used scanning electron microscopy and confocal laser scanning microscopy to generate a 3-D image of M. fermentans biofilm architecture structure as a thin monolayer of cells to several layers thick which contain water channels allowing the diffusion of nutrients and oxygen (Awadh et al, 2021). When Mmm attaches to a solid surface, it can produce biofilms.…”

Pathogenic avian mycoplasmas show phenotypic differences in their biofilm forming ability compared to non-pathogenic species in vitro

“…The architecture of the biofilm produced by other mycoplasmas has already been studied; M. pneumoniae is able to form volcano-like structures [ 28 ], while M. pulmonis creates tower structures in vitro [ 29 ]. Images taken with a scanning electron microscope of the biofilm produced by Mg during another study [ 15 ] showed the presence of lichen-like structures, which are very similar to those created by M. fermentans [ 30 ] and Ureaplasma parvum [ 31 ]. In another study on Ms [ 16 ], both mushroom-like and tower-like structures were observed in the biofilm, even though the authors investigated the biofilm produced as soon as the culture broth was acidified.…”

“…Therefore, increasing the knowledge about this mode of microbial life becomes fundamental, putting aside for a while the traditional single-cell-centric view of microbiology research. It is reported in the literature that at least fifteen mycoplasma species, of both human [ 30 , 32 ] and animal [ 14 , 15 , 29 , 33 , 42 ] origin, are capable of producing biofilm. The authors demonstrated that five more mycoplasma species are able to produce biofilm in vitro , even though the non-pathogenic avian mycoplasmas species showed to be less capable of expressing this phenotype compared to the pathogenic ones.…”

A Comprehensive Survey with Quantitative Comparison of Image Analysis Methods for Microorganism Biovolume Measurements

“…In [ 112 ], Minitab version 16 (Minitab Inc., USA) is applied to determine the biovolume of Mycoplasma fermentans . First, a median filter is used for noise removing in each slice of images.…”