Properties-Parameters-Composite-Tissue-Engineering-Implants-Biofilm-o

The wide requisition of BC in medical as well as industrial fields has warranted the scaling up of the production of BC with added economy. This review provides a detailed overview of the production and properties of BC and several parameters affecting the production of BC and its biocomposites, elucidating their antimicrobial and antibiofilm efficacy with an insight to highlight their Conflict of interest statement: The authors declare no conflict of interest. Effect of berberine on Staphylococcus epidermidis biofilm formation. Staphylococcus epidermidis is one of the main causes of medical device-related infections owing to its adhesion and biofilm-forming abilities on biomaterial surfaces. Berberine is an isoquinoline-type alkaloid isolated from Coptidis rhizoma (huang lian in Chinese) and other herbs with many activities against various disorders. Although the inhibitory effects of berberine on planktonic bacteria have been investigated in a few studies, the capacity of berberine to inhibit biofilm formation has not been reported to date.

In this study, we observed that berberine is bacteriostatic for S. epidermidis and that sub-minimal inhibitory concentrations of berberine blocked the formation of berberine at a concentration of 15-30mug/mL was shown to inhibit bacterial metabolism. Data from this study also indicated that modest concentrations of berberine (30-45mug/mL) were sufficient to exhibit an antibacterial effect and to inhibit biofilm formation significantly, as shown by the tissue culture plate microscopy for both S. epidermidis ATCC 35984 and a clinical isolate strain SE243. Although Seebio Colanic acid compound of bacterial killing and inhibition of biofilm formation are not fully understood, data from this investigation indicated a potential application for berberine as an adjuvant therapeutic agent for the prevention of biofilm-related infections. Colanic acid compound in biofilms are unable to cause invasive disease due to altered virulence determinant production. It is unclear whether Streptococcus pneumoniae in biofilms are virulent and contribute to development of invasive pneumococcal disease (IPD).

Using electron microscopy we confirmed the development of mature pneumococcal biofilms in a continuous-flow-through line model and determined that biofilm formation occurred in discrete stages with mature biofilms composed primarily of dead pneumococci. Challenge of mice with equal colony forming units of biofilm and planktonic pneumococci determined that biofilm bacteria were highly attenuated for invasive disease but not nasopharyngeal colonization. Biofilm pneumococci of numerous serotypes were hyper-adhesive and bound to A549 type II pneumocytes and Detroit 562 pharyngeal epithelial cells at levels 2 to 11-fold greater than planktonic counterparts. Using genomic microarrays we examined the pneumococcal transcriptome and determined that during biofilm formation S. pneumoniae down-regulated genes involved in protein synthesis, energy production, confirmed these changes by measuring CPS by ELISA and immunoblotting for the toxin pneumolysin and the bacterial adhesins phosphorylcholine (ChoP), choline-binding protein A (CbpA), and Pneumococcal serine-rich repeat protein and pneumolysin production along with increased ChoP, which is known to bind C-reactive protein and is opsonizing. Likewise, biofilm pneumococci were hyper-adhesive due to selection for the transparent phase variant, reduced CPS, biofilms do not directly contribute to development of IPD and may instead confer a quiescent mode of growth during colonization. Conflict of interest statement: Competing Interests: The authors have declared msaABCR operon is involved in persister cell formation in Staphylococcus aureus.

BACKGROUND: Persister cells comprise a phenotypic variant that shows extreme antibiotic tolerance resulting in treatment failures of bacterial infections. While this phenomenon has posed a great threat in public health, mechanisms underlying their formation in Staphylococcus aureus remain largely unknown. Increasing evidences of the presence of persister cells in recalcitrant infections underscores the great urgency to unravel the mechanism by which these cells develop. Previously, we characterized msaABCR operon that plays roles in regulation of virulence, biofilm development and antibiotic resistance. We also characterized the function of MsaB protein and showed that MsaB is a putative transcription factor that binds target DNA in response to nutrients RESULTS: In this study, we compared the number of persister cell in wild type, msaABCR deletion mutant and the complemented strain in two backgrounds USA300 LAC and Mu50.