A biofilm is an syntrophic community of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPSs). The cells within the biofilm produce the EPS components, which are typically a polymeric combination of extracellular polysaccharides, proteins, lipids and DNA. Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes".
Pseudomonas is a genus of Gram-negative bacteria belonging to the family Pseudomonadaceae in the class Gammaproteobacteria. The 313 members of the genus demonstrate a great deal of metabolic diversity and consequently are able to colonize a wide range of niches. Their ease of culture in vitro and availability of an increasing number of Pseudomonas strain genome sequences has made the genus an excellent focus for scientific research; the best studied species include P. aeruginosa in its role as an opportunistic human pathogen, the plant pathogen P. syringae, the soil bacterium P. putida, and the plant growth-promoting P. fluorescens, P. lini, P. migulae, and P. graminis.
A prophage is a bacteriophage genome that is integrated into the circular bacterial chromosome or exists as an extrachromosomal plasmid within the bacterial cell. Integration of prophages into the bacterial host is the characteristic step of the lysogenic cycle of temperate phages. Prophages remain latent in the genome through multiple cell divisions until activation by an external factor, such as UV light, leading to production of new phage particles that will lyse the cell and spread. As ubiquitous mobile genetic elements, prophages play important roles in bacterial genetics and evolution, such as in the acquisition of virulence factors.
Siderophores (Greek: "iron carrier") are small, high-affinity iron-chelating compounds that are secreted by microorganisms such as bacteria and fungi. They help the organism accumulate iron. Although a widening range of siderophore functions is now being appreciated, siderophores are among the strongest (highest affinity) Fe3+ binding agents known. Phytosiderophores are siderophores produced by plants.
The Pseudomonadaceae are a family of bacteria which includes the genera Azomonas, Azorhizophilus, Azotobacter, Mesophilobacter, Pseudomonas, and Rugamonas. The family Azotobacteraceae was recently reclassified into this family.
A slime layer in bacteria is an easily removable, unorganized layer of extracellular material that surrounds bacteria cells. Specifically, this consists mostly of exopolysaccharides, glycoproteins, and glycolipids. Therefore, the slime layer is considered as a subset of glycocalyx.
The bacterial capsule is a large structure common to many bacteria. It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell. It is a well-organized layer, not easily washed off, and it can be the cause of various diseases.
Pseudomonas aeruginosa is a common encapsulated, Gram-negative, aerobic–facultatively anaerobic, rod-shaped bacterium that can cause disease in plants and animals, including humans. A species of considerable medical importance, P. aeruginosa is a multidrug resistant pathogen recognized for its ubiquity, its intrinsically advanced antibiotic resistance mechanisms, and its association with serious illnesses – hospital-acquired infections such as ventilator-associated pneumonia and various sepsis syndromes. P. aeruginosa is able to selectively inhibit various antibiotics from penetrating its outer membrane - and has high resistance to several antibiotics, according to the World Health Organization P. aeruginosa poses one of the greatest threats to humans in terms of antibiotic resistance.
The Vi capsular polysaccharide vaccine is a typhoid vaccine recommended by the World Health Organization for the prevention of typhoid. The vaccine was first licensed in the US in 1994 and is made from the purified Vi capsular polysaccharide from the Ty2 Salmonella Typhi strain; it is a subunit vaccine.
Bacterial neuraminidase is type of neuraminidase and a virulence factor for many bacteria including Bacteroides fragilis and Pseudomonas aeruginosa. Its function is to cleave a sialic acid residue off ganglioside-GM1 turning it into asialo-GM1 to which type 4 pili bind preferentially.
The Pseudomon-1 RNA motif is a conserved RNA identified by bioinformatics. It is used by most species whose genomes have been sequenced and that are classified within the genus Pseudomonas, and is also present in Azotobacter vinelandii, a closely related species. It is presumed to function as a non-coding RNA. Pseudomon-1 RNAs consistently have a downstream rho-independent transcription terminator.
Bacterial small RNAs (bsRNA) are small RNAs produced by bacteria; they are 50- to 500-nucleotide non-coding RNA molecules, highly structured and containing several stem-loops. Numerous sRNAs have been identified using both computational analysis and laboratory-based techniques such as Northern blotting, microarrays and RNA-Seq in a number of bacterial species including Escherichia coli, the model pathogen Salmonella, the nitrogen-fixing alphaproteobacterium Sinorhizobium meliloti, marine cyanobacteria, Francisella tularensis, Streptococcus pyogenes, the pathogen Staphylococcus aureus, and the plant pathogen Xanthomonas oryzae pathovar oryzae. Bacterial sRNAs affect how genes are expressed within bacterial cells via interaction with mRNA or protein, and thus can affect a variety of bacterial functions like metabolism, virulence, environmental stress response, and structure.
Pyoverdines are fluorescent siderophores produced by certain pseudomonads. Pyoverdines are important virulence factors, and are required for pathogenesis in many biological models of infection. Their contributions to bacterial pathogenesis include providing a crucial nutrient, regulation of other virulence factors, supporting the formation of biofilms, and are increasingly recognized for having toxicity themselves.
In biology, a pathogen, in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ.
Urs Jenal is a Swiss Microbiologist and Professor at the Biozentrum University of Basel, Switzerland.
Barbara Hotham Iglewski was an American microbiologist. She was director of international programs at the University of Rochester Medical Center where she was a professor of microbiology and immunology.
Everett Peter Greenberg is an American microbiologist. He is the inaugural Eugene and Martha Nester Professor of Microbiology at the Department of Microbiology of the University of Washington School of Medicine. He is best known for his research on quorum sensing, and has received multiple awards for his work.
Laurence G. Rahme is an American microbiologist who is Professor of Surgery and Microbiology at Harvard Medical School (HMS). At Massachusetts General Hospital (MGH) she also holds the title of Director of the Molecular Surgical Laboratory as a microbiologist in the Department of Surgery and Molecular Biology. Additionally, she holds a Senior Scientific Staff position at Shriners Hospitals for Children-Boston.
Jessica A. Scoffield is an American microbiologist and an assistant professor in the Department of Microbiology at the University of Alabama at Birmingham School of Medicine. Scoffield studies the mechanisms by which oral commensal bacteria interfere with pathogenic bacterial growth in order to inform the development of active therapeutic tools to prevent drug resistant pathogen infection. In 2019, Scoffield became the inaugural recipient of the American Association for Dental Research Procter and Gamble Underrepresented Faculty Research Fellowship.
Kalai Mathee is a professor at Florida International University, joint editor-in-chief of the Journal of Medical Microbiology, and an elected fellow of the American Academy of Microbiology. She is known for her research on bacterial infections caused by Pseudomonas aeruginosa.
