Plasmid transfer in biofilms: a perspective on limitations and opportunities

Abstract

Biofilms dominate microbial life, and their importance for human health and the environment can no longer be dismissed. Nevertheless many of the processes governing this form of microbial growth are still poorly understood. This includes the horizontal exchange of genetic information, which is a major driver in bacterial evolution and rapid adaptation, exemplified by the alarming spread of multi-drug resistance among pathogens mediated by plasmids. Biofilms are often considered hot spot for horizontal gene transfer, yet several studies have shown that plasmid transfer is limited to the outer layers. On the basis of results from decades of research we analyse this paradox and discuss the mechanisms by which biofilm growth can promote the initial transfer of some plasmids, but also limit further plasmid invasion into the population or community. If we want to adequately promote or combat horizontal gene spread in biofilms, we need to gain better insight into the physicochemical and biological mechanisms that control this process.

Plasmid Transfer in the Ocean – A Case Study from the Roseobacter Group

“…Since it requires close physical contact between donor and recipient, it is thought to be restricted to hot spots like aggregates or surfaces, where bacteria form biofilms (Thibault and Top, 2016), have high cell densities and are metabolically active (Sobecky and Hazen, 2009). Studies until now have been restricted to microcosms (Aminov, 2011).…”

Experimental evidence of antimicrobial effect of silver-coated silicon urological catheters

“…на гидрофильных поверхностях в тонких биопленках выживает больше бактерий. На гидрофобных материалах, согласно дан ным литературы, число клеток в массивных биопленках может снижаться за счет неблагоприятных условий, та ких как недостаток кислорода и питательных веществ [2]. Известно, что микроорганизмы эффективнее закре пляются на поверхности, имеющей значения шерохова тости, близкие к размерам самой клетки [17].…”

“…Широкое применение в урологической практике биологических и искусственных материалов, на поверх ности которых формируются бактериальные биопленки, повышает риск персистенции возбудителя в организме [1]. Кроме того, в биопленках происходит активная пе редача генетического материала между бактериями, в результате которой могут формироваться новые, в том числе полирезистентные, субпопуляции микроорганиз мов [2]. На сегодняшний день остро стоит проблема ка тетерассоциированных инфекций мочевыводящих пу тей (КАИМП), которые чаще всего вызваны штаммами уропатогенной Escherichia coli (UPEC) [3].…”

Spatially resolved abundances of antibiotic resistance genes and intI1 in wastewater treatment biofilms

“…One relevant factor is oxygen availability, which is greatest at biofilm upper surfaces and may contribute significantly to transfer rates of MGEs (Król et al, 2011). Furthermore, plasmid invasion from external donors into biofilms has been found to occur primarily at upper surfaces where organisms are metabolically active and consistently replicating (Christensen et al, 1998;Haagensen, Hansen, Johansen, & Molin, 2002;Stalder & Top, 2016).…”