Quantitation of biofilm and planktonic life forms of coexisting periodontal species

Karched, Maribasappa; Bhardwaj, Radhika G.; Inbamani, Anandavalli. R; Asikainen, Sirkka

doi:10.1016/j.anaerobe.2015.04.013

Cited by 25 publications

(19 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is also important to note that there are different ways to evaluate the production of biofilms, including the congo red agar method, bioluminescent assay, air-liquid interface, microscopy examination, among others (Freeman et al 1989, Donlan et al 2001, Hassan et al 2011, Cabarkapa et al 2015, Karched et al 2015. A clear picture of attachment cannot be obtained without considering the effects of the substratum, conditioning films forming on the substratum, hydrodynamics of the aqueous medium, characteristics of the medium and various properties of the cell surface (Donlan 2002).…”

Section: Discussionmentioning

confidence: 99%

Evaluation of the biofilm formation capacity of Pasteurella multocida strains isolated from cases of fowl cholera and swine lungs and its relationship with pathogenicity

et al. 2017

View full text Add to dashboard Cite

Pasteurella multocida is a Gram-negative bacillus that causes economic losses due to the development of respiratory diseases in several animal species. Among the mechanisms of virulence, the formation of biofilms is an important factor for bacterial survival in hostile environments. Studies of biofilm formation by P. multocida are needed because P. multocida is an important pathogen involved in respiratory infections. However, in contrast to other microorganisms, few studies of biofilm formation have examined P. multocida. Studies comparing the pathogenicity of microbial strains as a function of their biofilm production capacity are also rare. Consequently, the aim of this study was to evaluate the biofilm formation capacity of 94 P. multocida strains isolated from cases of fowl cholera and from swine lungs on polystyrene plates. The associations of the biofilm formation capacity with the pathogenicity index (PI) in vivo and with the presence of four genes (screened by PCR) of the tad locus (tadB, tadD, tadE and tadG), described as adhesion markers, were also determined. Strains from both animal origins were able to form biofilms. However, most of the specimens (52.13%) were classified as weak producers, and more than 40% of the strains of P. multocida (40.42%) did not produce biofilms. There was no significant difference (p>0.05) in the degree of biofilm production between the two sources of isolation. Of the analyzed strains, 56.52% contained all four genes (tadB, tadD, tadE and tadG). The PI arithmetic mean of the strains classified as non-biofilm producers was significantly different (p<0.05) from the PI of moderate-producer strains. The PI of specimens classified as weak biofilm producers also differed significantly (p<0.05) from that of the moderate-producer strains. The results indicate that even though the P. multocida strains isolated from cases of fowl cholera and swine lungs formed biofilms on polystyrene surfaces, adhesion was usually weak. The genes tadB, tadD, tadE and tadG were not significantly associated (p>0.05) with the production of biofilms and with the origin of a given strain. Finally, low virulence strains may suggest a higher biofilm formation capacity on polystyrene plates.

show abstract

Section: Discussionmentioning

confidence: 99%

Evaluation of the biofilm formation capacity of Pasteurella multocida strains isolated from cases of fowl cholera and swine lungs and its relationship with pathogenicity

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The most extensively reported class of bacterial-bacterial interactions involves the oral microbiota. Due to the outstanding number of bacterial species comprising the oral flora, the MTP assay provides the easiest method with which to screen for synergistic or antagonistic interactions between numerous oral species [46]. For example, Soares et al grew a consortium of 35 different oral bacterial species involved in chronic periodontitis in a CBD to investigate the effects of different combinations of antimicrobials, whereby azithromycin and metronidazole were synergistic in killing compared with a single antibiotic alone [47].…”

Section: Notable Polymicrobial Studies In Static Systemsmentioning

confidence: 99%

Biofilm Models of Polymicrobial Infection

2015

View full text Add to dashboard Cite

Interactions between microbes are complex and play an important role in the pathogenesis of infections. These interactions can range from fierce competition for nutrients and niches to highly evolved cooperative mechanisms between different species that support their mutual growth. An increasing appreciation for these interactions, and desire to uncover the mechanisms that govern them, has resulted in a shift from monomicrobial to polymicrobial biofilm studies in different disease models. Here we provide an overview of biofilm models used to study select polymicrobial infections and highlight the impact that the interactions between microbes within these biofilms have on disease progression. Notable recent advances in the development of polymicrobial biofilm-associated infection models and challenges facing the study of polymicrobial biofilms are addressed. Polymicrobial interactions in biofilmsOver the past 2 decades there has been a revolutionary paradigm shift in the field of microbiology with the appreciation that bacteria present in most biological systems exist in biofilms, rather than in a free-living state. This understanding has dramatically changed the way we study bacteria in the laboratory and resulted in the development of many new experimental systems that replicate biofilm environments [1][2][3][4][5]. Studies utilizing these systems have demonstrated time and time again that bacteria behave very differently when in a biofilm than during planktonic growth. In many ways, we now have to relearn everything we thought we knew about bacterial behavior through the view of the biofilm lens.Similarly, the recent explosion of metagenomic studies has significantly increased our appreciation of the complexity of the microbial populations present in biofilms [6,7]. This is also true for infections, most of which are thought to be biofilm related and inherently polymicrobial, including various species of bacteria, fungi and viruses [8]. It is thought that microbes act in concert to establish biofilms, which in turn can increase tolerance to antimicrobials, exacerbate of the host's immune response and increase persistence at the infection site [7,[9][10][11].Genetic diversity of microbes within biofilm communities is thought to increase the fitness of the residing community, making them more equipped to survive environmental stresses. In large part, this is due to an expanded gene pool, which can be more easily shared within the confines of a biofilm community [12]. Community composition and interactions within the community can have huge influences on bacterial behavior. Thus, just as the behavior of planktonic versus biofilm-associated bacteria is dramatically different, so is that of bacteria in single species versus multispecies systems.Interactions between microbes are complex and highly dependent on context. They can range from fierce competition for nutrients and niches, manifested by antagonistic behavior, to highly evolved cooperative mechanisms between different species that support their mutual grow...

show abstract

“…Aliquots for 1 week, and 2 and 6 months were preserved at -80 C, while those for 0 day were immediately subjected to DNA concentration measurement using NanoDrop TM presented below and bacterial quantification by qPCR as described below. Genomic DNA from reference bacterial strains was purified as described earlier (Karched, Bhardwaj, Inbamani, & Asikainen, 2015).…”

Section: Dna Purificationmentioning

confidence: 99%

“…For qPCR quantification of the 6 oral species, previously validated species-specific primers (Table 1) were chosen and their specificity revalidated using in silico analysis tools as described (Karched et al, 2015). The reactions were performed on ABI 7500 Fast Real-Time PCR machine.…”

Section: Qpcrmentioning

confidence: 99%