Comparative Screening of Digestion Tract Toxic Genes in Proteus mirabilis

Abstract

Proteus mirabilis is a common urinary tract pathogen, and may induce various inflammation symptoms. Its notorious ability to resist multiple antibiotics and to form urinary tract stones makes its treatment a long and painful process, which is further challenged by the frequent horizontal gene transferring events in P. mirabilis genomes. Three strains of P. mirabilis C02011/C04010/C04013 were isolated from a local outbreak of a food poisoning event in Shenzhen, China. Our hypothesis is that new genes may have been acquired horizontally to exert the digestion tract infection and toxicity. The functional characterization of these three genomes shows that each of them independently acquired dozens of virulent genes horizontally from the other microbial genomes. The representative strain C02011 induces the symptoms of both vomit and diarrhea, and has recently acquired a complete type IV secretion system and digestion tract toxic genes from the other bacteria.

Characterization of a Novel Diarrheagenic Strain of Proteus mirabilis Associated With Food Poisoning in China

“…According to the investigation of SZCDC, P. mirabilis C02011 was isolated from the residue food (cold dishes), vomited matter, excrement, and anal swab of the patients. Results of pulsed-field gel electrophoresis (PFGE) indicated that P. mirabilis C02011 was associated with this food poisoning case (Shi et al, 2016).…”

“…In our study, food samples, stool specimens, and vomit specimens collected from the patients were sent to the laboratory for examination within 24 h. Based on the phenotypic properties of morphology and biochemical features (WS/T 9-1996: Diagnostic criterion and principles of food poisoning induced by P. mirabilis; GB/T4789-2003: National criterion for food microbiological examination), P. mirabilis was successfully identified from the food poisoning incident (Shi et al, 2016). Meanwhile, Sensititre Auto-reader (Sensititre, United Kingdom) system was used to detect the bacteria.…”

“…Strains involved in the study were isolated from various sources in SZCDC (Shi et al, 2016). P. mirabilis C02011 strain was isolated from patients' specimens in a food poisoning in Shenzhen, whereas P. mirabilis B02005 was isolated from the anal swab of a healthy individual with no clinical symptoms.…”

“…In recent years, more and more food poisoning cases associated with P. mirabilis had been reported in China. In these food poisoning incidents, clinical symptoms of the patients infected with P. mirabilis included abdominal pain, diarrhea, nausea, and dizziness (Wang et al, 2010;Shi et al, 2014Shi et al, , 2016. For example, 256 students in a middle school were diagnosed with food poisoning of P. mirabilis in Zhejiang Province in 1998 (Liu and Lu, 2000); 34 people were diagnosed with food poisoning of P. mirabilis in Guangxi Province in 2006 (Liang et al, 2007); and four people were identified to have food poisoning of P. mirabilis in Beijing in 2013 (Huo et al, 2014).…”

“…In our study, two strains of P. mirabilis have been isolated from clinical specimens: P. mirabilis C02011 strain was isolated from patients' vomitus and feces specimens in a food poisoning in Shenzhen; and P. mirabilis B02005 strain was isolated from feces specimen of healthy people. Our preliminary works (Shi et al, 2014(Shi et al, , 2016 have confirmed our speculation that several virulence genes (urease gene, hemolysin gene, and metalloproteinase gene) were detected in P. mirabilis C02011 by using whole genome sequencing and phylogenetic analysis, which were not found in P. mirabilis B02005 strain (Shi et al, 2016). Notably, type IV secretion system (T4SS), which is commonly found in pathogenic bacteria such as Klebsiella pneumoniae and Helicobacter pylori (Wang et al, 2016;Medrano and Bell, 2017), has also been identified in P. mirabilis C02011 (Shi et al, 2016).…”