Prophage Spontaneous Activation Promotes DNA Release Enhancing Biofilm Formation in Streptococcus pneumoniae
نویسندگان
چکیده
Streptococcus pneumoniae (pneumococcus) is able to form biofilms in vivo and previous studies propose that pneumococcal biofilms play a relevant role both in colonization and infection. Additionally, pneumococci recovered from human infections are characterized by a high prevalence of lysogenic bacteriophages (phages) residing quiescently in their host chromosome. We investigated a possible link between lysogeny and biofilm formation. Considering that extracellular DNA (eDNA) is a key factor in the biofilm matrix, we reasoned that prophage spontaneous activation with the consequent bacterial host lysis could provide a source of eDNA, enhancing pneumococcal biofilm development. Monitoring biofilm growth of lysogenic and non-lysogenic pneumococcal strains indicated that phage-infected bacteria are more proficient at forming biofilms, that is their biofilms are characterized by a higher biomass and cell viability. The presence of phage particles throughout the lysogenic strains biofilm development implicated prophage spontaneous induction in this effect. Analysis of lysogens deficient for phage lysin and the bacterial major autolysin revealed that the absence of either lytic activity impaired biofilm development and the addition of DNA restored the ability of mutant strains to form robust biofilms. These findings establish that limited phage-mediated host lysis of a fraction of the bacterial population, due to spontaneous phage induction, constitutes an important source of eDNA for the S. pneumoniae biofilm matrix and that this localized release of eDNA favors biofilm formation by the remaining bacterial population.
منابع مشابه
The BR domain of PsrP interacts with extracellular DNA to promote bacterial aggregation; structural insights into pneumococcal biofilm formation
The major human pathogen Streptococcus pneumoniae is a leading cause of disease and death worldwide. Pneumococcal biofilm formation within the nasopharynx leads to long-term colonization and persistence within the host. We have previously demonstrated that the capsular surface-associated pneumococcal serine rich repeat protein (PsrP), key factor for biofilm formation, binds to keratin-10 (KRT10...
متن کاملCharacterization of hydrogen peroxide-induced DNA release by Streptococcus sanguinis and Streptococcus gordonii.
Extracellular DNA (eDNA) is produced by several bacterial species and appears to contribute to biofilm development and cell-cell adhesion. We present data showing that the oral commensals Streptococcus sanguinis and Streptococcus gordonii release DNA in a process induced by pyruvate oxidase-dependent production of hydrogen peroxide (H(2)O(2)). Surprisingly, S. sanguinis and S. gordonii cell int...
متن کاملBiofilm formation in Streptococcus pneumoniae
Biofilm-grown bacteria are refractory to antimicrobial agents and show an increased capacity to evade the host immune system. In recent years, studies have begun on biofilm formation by Streptococcus pneumoniae, an important human pathogen, using a variety of in vitro model systems. The bacterial cells in these biofilms are held together by an extracellular matrix composed of DNA, proteins and,...
متن کاملShin'iseihaito (Xinyiqingfeitang) Suppresses the Biofilm Formation of Streptococcus pneumoniae In Vitro
Streptococcus pneumoniae (S. pneumoniae) is the important pathogen that causes otolaryngeal diseases such as sinusitis. S. pneumoniae frequently forms the biofilm to prevent severe circumstances such as antimicrobial agents. Shin'iseihaito (xinyiqingfeitang) is a formula of Japanese traditional Kampo medicine that has 9 crude drugs and provides the medicinal usage for sinusitis. The objective o...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 5 شماره
صفحات -
تاریخ انتشار 2010