title: Insights on Klebsiella pneumoniae Biofilms Assembled on Different Surfaces Using Phenotypic and Genotypic Approaches.
abstract: Klebsiella pneumoniaeis a prominent etiological agent of healthcare associated infections (HAIs). In this context, multidrug-resistant and biofilm-producing bacteria are of special public health concern due to the difficulties associated with treatment of human infections and eradication from hospital environments. Here, in order to study the impact of medical devices-associated materials on the biofilm dynamics, we performed biofilm phenotypic analyses through a classic and a new scanning electron microscopy (SEM) technique for three multidrug-resistantK. pneumoniaeisolates growing on polystyrene and silicone. We also applied whole-genome sequencing (WGS) to search for genetic clues underlying biofilm phenotypic differences. We found major differences in the extracellular polymeric substances (EPS) content among the three strains, which were further corroborated by in-depth EPS composition analysis. WGS analysis revealed a high nucleotide similarity within the core-genome, but relevant differences in the accessory genome that may account for the detected biofilm phenotypic dissimilarities, such as genes already associated with biofilm formation in other pathogenic bacteria (e.g., genes coding haemogglutinins and haemolysins). These data reinforce that the research efforts to defeat bacterial biofilms should take into account that their dynamics may be contingent on the medical devices-associated materials.
authors.affiliation: Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Saúde Ambiental, Unidade de Investigação e Desenvolvimento-Lisboa, Avenida Padre Cruz, 1649-016 Lisboa, Portugal. mariamfbandeira@gmail.com.|Universidade de Lisboa, Instituto Superior Técnico, Departamento de Engenharia Química, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal. mariamfbandeira@gmail.com.
authors.forename: Maria
authors.initials: M
authors.lastname: Bandeira
authors.affiliation: Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Doenças Infeciosas, Núcleo de Bioinformática, Avenida Padre Cruz, 1649-016 Lisboa, Portugal. vitor.borges@insa.min-saude.pt.
authors.forename: Vítor
authors.initials: V
authors.lastname: Borges
authors.affiliation: Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Doenças Infeciosas, Núcleo de Bioinformática, Avenida Padre Cruz, 1649-016 Lisboa, Portugal. j.paulo.gomes@insa.min-saude.pt.
authors.forename: João P
authors.initials: JP
authors.lastname: Gomes
authors.affiliation: Universidade de Lisboa, Faculdade de Farmácia, Av Prof Gama Pinto, 1649-003 Lisboa, Portugal. aduarte@ff.ul.pt.
authors.forename: Aida
authors.initials: A
authors.lastname: Duarte
authors.affiliation: Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Saúde Ambiental, Unidade de Investigação e Desenvolvimento-Lisboa, Avenida Padre Cruz, 1649-016 Lisboa, Portugal. maria.jordao@insa.min-saude.pt.
authors.forename: Luisa
authors.initials: L
authors.lastname: Jordao
keywords: Klebsiella pneumoniae; biofilms; electron microscopy; extracellular polymeric substances (EPS); healthcare associated infections (HAIs); whole genome sequencing (WGS)