A crucial role for exopolysaccharide modification in bacterial biofilm formation, immune evasion, and virulence.

The influence of microorganisms growing as sessile communities in a large number of human infections has been extensively studied and recognized for 30-40 years, therefore warranting intense scientific and medical research. Nonetheless, mimicking the biofilm-life style of bacteria and biofilm-related infections has been an arduous task. Models used to study biofilms range from simple in vitro to complex in vivo models of tissues or device-related infections. These different models have progressively contributed to the current knowledge of biofilm physiology within the host context. While far from a complete understanding of the multiple elements controlling the dynamic interactions between the host and biofilms, we are nowadays witnessing the emergence of promising preventive or curative strategies to fight biofilm-related infections. This review undertakes a comprehensive analysis of the literature from a historic perspective commenting on the contribution of the different models and discussing future venues and new approaches that can be merged with more traditional techniques in order to model biofilm-infections and efficiently fight them.

https://www.mdpi.com/2076-0817/2/2/288/pdf

From in vitro to in vivo Models of Bacterial Biofilm-Related Infections

In vitro and in vivo model systems to study microbial biofilm formation

Bioluminescence (BL) is a spectacular phenomenon involving light emission by live organisms. It is caused by the oxidation of a small organic molecule, luciferin, with molecular oxygen, which is catalysed by the enzyme luciferase. In nature, there are approximately 30 different BL systems, of which only 9 have been studied to various degrees in terms of their reaction mechanisms. A vast range of in vitro and in vivo analytical techniques have been developed based on BL, including tests for different analytes, immunoassays, gene expression assays, drug screening, bioimaging of live organisms, cancer studies, the investigation of infectious diseases and environmental monitoring. This review aims to cover the major existing applications for bioluminescence in the context of the diversity of luciferases and their substrates, luciferins. Particularly, the properties and applications of D-luciferin, coelenterazine, bacterial, Cypridina and dinoflagellate luciferins and their analogues along with their corresponding luciferases are described. Finally, four other rarely studied bioluminescent systems (those of limpet Latia, earthworms Diplocardia and Fridericia and higher fungi), which are promising for future use, are also discussed.

1001 lights: luciferins, luciferases, their mechanisms of action and applications in chemical analysis, biology and medicine

Azithromycin Synergizes with Cationic Antimicrobial Peptides to Exert Bactericidal and Therapeutic Activity Against Highly Multidrug-Resistant Gram-Negative Bacterial Pathogens

Microbial adhesion and biofilm formation on medical implants is a common occurrence and represents a serious medical problem. Since biofilm microorganisms are difficult to eradicate with antibiotic therapy, chronic, recurrent infections often develop. With the increased use of prosthetic biomedical implants, chronic nosocomial infections have become prevalent in recent years (9, 41). Bacterial colonization of indwelling devices can be a prelude to both systemic infection and malfunction of the device.

A variety of techniques, such as direct microscopic enumeration, total viable count, metabolically active dyes, radiochemistry, and fluorescence, have been used to investigate microbial biofilms (1, 4, 8, 14, 17, 18, 23, 29, 33, 38). While some of these methods are useful for in vitro studies, they have not proved ideal for the investigation of biofilms in experimental infection models. The difficulty in analyzing biofilms in vivo lies in the lack of tools that allow noninvasive longitudinal study design. Assays developed to date, both direct and indirect, are time-consuming and laborious and involve the extraction of bacteria from support surfaces. To better understand and control biofilms on medical devices, rapid, direct, nondestructive, real-time quantitative monitoring methods that are adaptable to the clinical situation are needed. These assays may be used to develop new preventive and therapeutic methods to combat biofilm related infections.

To this end, bioluminescent reporters offer a method of labeling pathogens that is innocuous and allows the sensitive detection of only live, metabolically active cells by optical biophotonic imaging. Since bacterial luciferase requires reduced flavin mononucleotide for the generation of bioluminescence within the cell, it is a good indicator of the metabolic state of cells (22). Many biological applications of bioluminescent and fluorescent reporter gene systems have been developed during the last few years (1, 3, 10, 14, 19-23, 26-28, 33, 35-38). Monitoring a disease process in a living animal by using bioluminescent-tagged pathogens was first demonstrated in 1995 by Contag et al. (5). This noninvasive, rapid, real-time monitoring approach has been applied to a myriad of animal infection models and has proven to have significant advantages over conventional methods for studying disease and treatment in animals (6, 7, 11, 12, 31).

Monitoring bioluminescence as a measure of metabolic activity provides a rapid, quantitative in situ measure of biofilm development and physiological activities of bacteria within biofilms. In this study, we describe the detection of bioluminescent strains of Staphylococcus aureus and Pseudomonas aeruginosa, two of the most predominant biofilm-forming pathogens, using real-time monitoring to nondestructively, image catheter-based infections in an experimental animal model.

(Parts of the present study were presented at the 102nd General Meeting of the American Society for Microbiology, abstr. J6, 2002.)

https://iai.asm.org/content/iai/71/2/882.full.pdf

Direct continuous method for monitoring biofilm infection in a mouse model

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Michael Rubin

Author Tools

Chat about Author

Papers

Direct continuous method for monitoring biofilm infection in a mouse model