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Microbiology Spectrum Oct 2015Proteus mirabilis is a Gram-negative bacterium and is well known for its ability to robustly swarm across surfaces in a striking bulls'-eye pattern. Clinically, this... (Review)
Review
Proteus mirabilis is a Gram-negative bacterium and is well known for its ability to robustly swarm across surfaces in a striking bulls'-eye pattern. Clinically, this organism is most frequently a pathogen of the urinary tract, particularly in patients undergoing long-term catheterization. This review covers P. mirabilis with a focus on urinary tract infections (UTI), including disease models, vaccine development efforts, and clinical perspectives. Flagella-mediated motility, both swimming and swarming, is a central facet of this organism. The regulation of this complex process and its contribution to virulence is discussed, along with the type VI-secretion system-dependent intra-strain competition, which occurs during swarming. P. mirabilis uses a diverse set of virulence factors to access and colonize the host urinary tract, including urease and stone formation, fimbriae and other adhesins, iron and zinc acquisition, proteases and toxins, biofilm formation, and regulation of pathogenesis. While significant advances in this field have been made, challenges remain to combatting complicated UTI and deciphering P. mirabilis pathogenesis.
Topics: Animals; Catheter-Related Infections; Disease Models, Animal; Humans; Locomotion; Proteus Infections; Proteus mirabilis; Urinary Tract Infections; Virulence; Virulence Factors
PubMed: 26542036
DOI: 10.1128/microbiolspec.UTI-0017-2013 -
EcoSal Plus Feb 2018, a Gram-negative rod-shaped bacterium most noted for its swarming motility and urease activity, frequently causes catheter-associated urinary tract infections (CAUTIs)... (Review)
Review
, a Gram-negative rod-shaped bacterium most noted for its swarming motility and urease activity, frequently causes catheter-associated urinary tract infections (CAUTIs) that are often polymicrobial. These infections may be accompanied by urolithiasis, the development of bladder or kidney stones due to alkalinization of urine from urease-catalyzed urea hydrolysis. Adherence of the bacterium to epithelial and catheter surfaces is mediated by 17 different fimbriae, most notably MR/P fimbriae. Repressors of motility are often encoded by these fimbrial operons. Motility is mediated by flagella encoded on a single contiguous 54-kb chromosomal sequence. On agar plates, undergoes a morphological conversion to a filamentous swarmer cell expressing hundreds of flagella. When swarms from different strains meet, a line of demarcation, a "Dienes line," develops due to the killing action of each strain's type VI secretion system. During infection, histological damage is caused by cytotoxins including hemolysin and a variety of proteases, some autotransported. The pathogenesis of infection, including assessment of individual genes or global screens for virulence or fitness factors has been assessed in murine models of ascending urinary tract infections or CAUTIs using both single-species and polymicrobial models. Global gene expression studies performed in culture and in the murine model have revealed the unique metabolism of this bacterium. Vaccines, using MR/P fimbria and its adhesin, MrpH, have been shown to be efficacious in the murine model. A comprehensive review of factors associated with urinary tract infection is presented, encompassing both historical perspectives and current advances.
Topics: Animals; Bacterial Vaccines; Catheter-Related Infections; Disease Models, Animal; Fimbriae, Bacterial; Host-Pathogen Interactions; Humans; Mice; Proteus Infections; Proteus mirabilis; Urinary Tract Infections; Virulence
PubMed: 29424333
DOI: 10.1128/ecosalplus.ESP-0009-2017 -
Frontiers in Cellular and Infection... 2022The human gut acts as the main reservoir of microbes and a relevant source of life-threatening infections, especially in immunocompromised patients. There, the...
The human gut acts as the main reservoir of microbes and a relevant source of life-threatening infections, especially in immunocompromised patients. There, the opportunistic fungal pathogen adapts to the host environment and additionally interacts with residing bacteria. We investigated fungal-bacterial interactions by coinfecting enterocytes with the yeast and the Gram-negative bacterium resulting in enhanced host cell damage. This synergistic effect was conserved across different isolates and occurred also with non- species and mutants defective in filamentation or candidalysin production. Using bacterial deletion mutants, we identified the hemolysin HpmA to be the key effector for host cell destruction. Spatially separated coinfections demonstrated that synergism between and is induced by contact, but also by soluble factors. Specifically, we identified -mediated glucose consumption and farnesol production as potential triggers for virulence. In summary, our study demonstrates that coinfection of enterocytes with and can result in increased host cell damage which is mediated by bacterial virulence factors as a result of fungal niche modification nutrient consumption and production of soluble factors. This supports the notion that certain fungal-bacterial combinations have the potential to result in enhanced virulence in niches such as the gut and might therefore promote translocation and dissemination.
Topics: Candida; Candida albicans; Coinfection; Enterocytes; Humans; Proteus mirabilis
PubMed: 35651758
DOI: 10.3389/fcimb.2022.866416 -
MSystems Aug 2023is a Gram-negative bacterium recognized for its unique swarming motility and urease activity. A previous proteomic report on four strains hypothesized that, unlike...
is a Gram-negative bacterium recognized for its unique swarming motility and urease activity. A previous proteomic report on four strains hypothesized that, unlike other Gram-negative bacteria, may not exhibit significant intraspecies variation in gene content. However, there has not been a comprehensive analysis of large numbers of genomes from various sources to support or refute this hypothesis. We performed comparative genomic analysis on 2,060 genomes. We sequenced the genomes of 893 isolates recovered from clinical specimens from three large US academic medical centers, combined with 1,006 genomes from NCBI Assembly and 161 genomes assembled from Illumina reads in the public domain. We used average nucleotide identity (ANI) to delineate species and subspecies, core genome phylogenetic analysis to identify clusters of highly related genomes, and pan-genome annotation to identify genes of interest not present in the model strain HI4320. Within our cohort, is composed of 10 named species and 5 uncharacterized genomospecies. can be subdivided into three subspecies; subspecies 1 represented 96.7% (1,822/1,883) of all genomes. The pan-genome includes 15,399 genes outside of HI4320, and 34.3% (5,282/15,399) of these genes have no putative assigned function. Subspecies 1 is composed of several highly related clonal groups. Prophages and gene clusters encoding putatively extracellular-facing proteins are associated with clonal groups. Uncharacterized genes not present in the model strain HI4320 but with homology to known virulence-associated operons can be identified within the pan-genome. IMPORTANCE Gram-negative bacteria use a variety of extracellular facing factors to interact with eukaryotic hosts. Due to intraspecies genetic variability, these factors may not be present in the model strain for a given organism, potentially providing incomplete understanding of host-microbial interactions. In contrast to previous reports on , but similar to other Gram-negative bacteria, has a mosaic genome with a linkage between phylogenetic position and accessory genome content. encodes a variety of genes that may impact host-microbe dynamics beyond what is represented in the model strain HI4320. The diverse, whole-genome characterized strain bank from this work can be used in conjunction with reverse genetic and infection models to better understand the impact of accessory genome content on bacterial physiology and pathogenesis of infection.
Topics: Humans; Proteus mirabilis; Proteomics; Phylogeny; Virulence; Virulence Factors
PubMed: 37341494
DOI: 10.1128/msystems.00159-23 -
Journal of Molecular Biology Nov 2015Flagella propel bacteria during both swimming and swarming, dispersing them widely. However, while swimming bacteria use chemotaxis to find nutrients and avoid toxic... (Review)
Review
Flagella propel bacteria during both swimming and swarming, dispersing them widely. However, while swimming bacteria use chemotaxis to find nutrients and avoid toxic environments, swarming bacteria appear to suppress chemotaxis and to use the dynamics of their collective motion to continuously expand and acquire new territory, barrel through lethal chemicals in their path, carry along bacterial and fungal cargo that assists in exploration of new niches, and engage in group warfare for niche dominance. Here, we focus on two aspects of swarming, which, if understood, hold the promise of revealing new insights into microbial signaling and behavior, with ramifications beyond bacterial swarming. These are as follows: how bacteria sense they are on a surface and turn on programs that promote movement and how they override scarcity and adversity as dense packs.
Topics: Anti-Bacterial Agents; Bacillus subtilis; Bacterial Physiological Phenomena; Chemotaxis; Drug Resistance, Bacterial; Escherichia coli; Flagella; Proteus mirabilis; Salmonella; Vibrio parahaemolyticus
PubMed: 26277623
DOI: 10.1016/j.jmb.2015.07.025 -
Urologia Internationalis 2021Proteus mirabilis (PM) is a Gram-negative rod-shaped bacterium and widely exists in the natural environment, and it is most noted for its swarming motility and urease... (Review)
Review
Proteus mirabilis (PM) is a Gram-negative rod-shaped bacterium and widely exists in the natural environment, and it is most noted for its swarming motility and urease activity. PM is the main pathogen causing complicated urinary tract infections (UTIs), especially catheter-associated urinary tract infections. Clinically, PM can form a crystalline biofilm on the outer surface and inner cavity of the urethral indwelling catheter owing to its ureolytic biomineralization. This leads to catheter encrustation and blockage and, in most cases, is accompanied by urine retention and ascending UTI, causing cystitis, pyelonephritis, and the development of bladder or kidney stones, or even fatal complications such as septicemia and endotoxic shock. In this review, we discuss how PM is mediated by a catheter into the urethra, bladder, and then rose to the kidney causing UTI and the main virulence factors associated with different stages of infection, including flagella, pili or adhesins, urease, hemolysin, metal intake, and immune escape, encompassing both historical perspectives and current advances.
Topics: Catheter-Related Infections; Humans; Proteus Infections; Proteus mirabilis; Urinary Catheters; Urinary Tract Infections
PubMed: 33691318
DOI: 10.1159/000514097 -
Nature Reviews. Microbiology Nov 2012Proteus mirabilis, named for the Greek god who changed shape to avoid capture, has fascinated microbiologists for more than a century with its unique swarming... (Review)
Review
Proteus mirabilis, named for the Greek god who changed shape to avoid capture, has fascinated microbiologists for more than a century with its unique swarming differentiation, Dienes line formation and potent urease activity. Transcriptome profiling during both host infection and swarming motility, coupled with the availability of the complete genome sequence for P. mirabilis, has revealed the occurrence of interbacterial competition and killing through a type VI secretion system, and the reciprocal regulation of adhesion and motility, as well as the intimate connections between metabolism, swarming and virulence. This Review addresses some of the unique and recently described aspects of P. mirabilis biology and pathogenesis, and emphasizes the potential role of this bacterium in single-species and polymicrobial urinary tract infections.
Topics: Bacterial Adhesion; Bacterial Proteins; Bacterial Secretion Systems; Catheter-Related Infections; Gene Expression Regulation, Bacterial; Gene Transfer, Horizontal; Humans; Immune Evasion; Proteus Infections; Proteus mirabilis; Urinary Tract Infections; Virulence Factors
PubMed: 23042564
DOI: 10.1038/nrmicro2890 -
BMC Microbiology Aug 2023Proteus mirabilis, a naturally resistant zoonotic bacterium belonging to the Enterobacteriaceae family, has exhibited an alarming increase in drug resistance....
Proteus mirabilis, a naturally resistant zoonotic bacterium belonging to the Enterobacteriaceae family, has exhibited an alarming increase in drug resistance. Consequently, there is an urgent need to explore alternative antimicrobial agents. Bacteriophages, viruses that selectively target bacteria, are abundant in the natural environment and have demonstrated potential as a promising alternative to antibiotics. In this study, we successfully isolated four strains of Proteus mirabilis phages from sewage obtained from a chicken farm in Sichuan, China. Subsequently, we characterized one of the most potent lytic phages, Q29, by examining its biological and genomic features. Comparative genomic analysis revealed the functional genes and phylogenetic evolution of Q29 phages. Our findings revealed that Proteus mirabilis bacteriophage Q29 possesses an icosahedral symmetrical head with a diameter of 95 nm and a tail length of 240 nm. Moreover, phage Q29 exhibited stability within a temperature range of 37 ℃ to 55 ℃ and under pH conditions ranging from 4 to 9. The optimal multiplicity of infection (MOI) for this phage was determined to be 0.001. Furthermore, the one-step growth curve results indicated an incubation period of approximately 15 min, an outbreak period of approximately 35 min, and an average cleavage quantity of approximately 60 plaque-forming units (PFU) per cell. The genome of phage Q29 was found to have a total length of 58,664 base pairs and encoded 335 open reading frames (ORFs) without carrying any antibiotic resistance genes. Additionally, genetic evolutionary analysis classified phage Q29 within the family Caudalidae and the genus Myotail. This study provides valuable research material for further development of Proteus mirabilis bacteriophage biologics as promising alternatives to antibiotics, particularly in light of the growing challenge of antibiotic resistance posed by this bacterium.
Topics: Bacteriophages; Proteus mirabilis; Phylogeny; Genomics; Anti-Bacterial Agents; Genome, Viral
PubMed: 37553593
DOI: 10.1186/s12866-023-02960-4 -
MSphere Aug 2021Many bacterial species employ systems for interference competition with other microorganisms. Some systems are effective without contact (e.g., through secretion of...
Many bacterial species employ systems for interference competition with other microorganisms. Some systems are effective without contact (e.g., through secretion of toxins), while other systems (e.g., type VI secretion system [T6SS]) require direct contact between cells. Here, we provide the initial characterization of a novel contact-dependent competition system for Proteus mirabilis. In neonatal mice, a commensal P. mirabilis strain apparently eliminated commensal Escherichia coli. We replicated the phenotype and showed that P. mirabilis efficiently reduced the viability of several species but not Gram-positive species or yeast cells. Importantly, P. mirabilis strains isolated from humans also killed E. coli. A reduction of viability occurred from early stationary phase to 24 h of culture and was observed in shaking liquid media as well as on solid media. Killing required contact but was independent of T6SS, which is the only contact-dependent killing system described for P. mirabilis. Expression of the killing system was regulated by osmolarity and components secreted into the supernatant. Stationary-phase P. mirabilis culture supernatant itself did not kill but was sufficient to induce killing in an exponentially growing coculture. In contrast, killing was largely prevented in media with low osmolarity. In summary, we provide the initial characterization of a potentially novel interbacterial competition system used by P. mirabilis. The study of bacterial competition systems has received significant attention in recent years. These systems are important in a multitude of polymicrobial environments and collectively shape the composition of complex ecosystems like the mammalian gut. They are also being explored as narrow-spectrum alternatives to specifically eliminate problematic pathogenic species. However, only a small fraction of the estimated number of interbacterial competition systems has been identified. We discovered a competition system that is novel for Proteus mirabilis. Inspired by an observation in infant mice, we confirmed that P. mirabilis was able to efficiently kill several species. This killing system might represent a new function of a known competition system or even a novel system, as the observed characteristics do not fit with described contact-dependent competition systems. Further characterization of this system might help understand how P. mirabilis competes with other in various niches.
Topics: Animals; Animals, Newborn; Culture Media; Enterobacteriaceae; Female; Male; Mice; Mice, Inbred C57BL; Microbial Interactions; Microbial Viability; Phenotype; Proteus mirabilis; Specific Pathogen-Free Organisms; Type VI Secretion Systems
PubMed: 34319125
DOI: 10.1128/mSphere.00321-21 -
Polish Journal of Microbiology May 2022Spaceflight missions affect the behavior of microbes that are inevitably introduced into space environments and may impact astronauts' health. Current studies have...
Spaceflight missions affect the behavior of microbes that are inevitably introduced into space environments and may impact astronauts' health. Current studies have mainly focused on the biological characteristics and molecular mechanisms of microbes after short-term or long-term spaceflight, but few have compared the impact of various lengths of spaceflight missions on the characteristics of microbes. Researchers generally agree that microgravity (MG) is the most critical factor influencing microbial physiology in space capsules during flight missions. This study compared the growth behavior and transcriptome profile of cells exposed to long-term simulated microgravity (SMG) with those exposed to short-term SMG. The results showed that long-term SMG decreased the growth rate, depressed biofilm formation ability, and affected several transcriptomic profiles, including stress response, membrane transportation, metal ion transportation, biological adhesion, carbohydrate metabolism, and lipid metabolism in contrast to short-term SMG. This study improved the understanding of long-term versus short-term SMG effects on behavior and provided relevant references for analyzing the influence of on astronaut health during spaceflights.
Topics: Gene Expression Profiling; Proteus mirabilis; Space Flight; Transcriptome; Weightlessness
PubMed: 35635525
DOI: 10.33073/pjm-2022-015