Whole-genome sequencing and identification of Morganella morganii KT pathogenicity-related genes

Abstract

BackgroundThe opportunistic enterobacterium, Morganella morganii, which can cause bacteraemia, is the ninth most prevalent cause of clinical infections in patients at Changhua Christian Hospital, Taiwan. The KT strain of M. morganii was isolated during postoperative care of a cancer patient with a gallbladder stone who developed sepsis caused by bacteraemia. M. morganii is sometimes encountered in nosocomial settings and has been causally linked to catheter-associated bacteriuria, complex infections of the urinary and/or hepatobiliary tracts, wound infection, and septicaemia. M. morganii infection is associated with a high mortality rate, although most patients respond well to appropriate antibiotic therapy. To obtain insights into the genome biology of M. morganii and the mechanisms underlying its pathogenicity, we used Illumina technology to sequence the genome of the KT strain and compared its sequence with the genome sequences of related bacteria.ResultsThe 3,826,919-bp sequence contained in 58 contigs has a GC content of 51.15% and includes 3,565 protein-coding sequences, 72 tRNA genes, and 10 rRNA genes. The pathogenicity-related genes encode determinants of drug resistance, fimbrial adhesins, an IgA protease, haemolysins, ureases, and insecticidal and apoptotic toxins as well as proteins found in flagellae, the iron acquisition system, a type-3 secretion system (T3SS), and several two-component systems. Comparison with 14 genome sequences from other members of Enterobacteriaceae revealed different degrees of similarity to several systems found in M. morganii. The most striking similarities were found in the IS4 family of transposases, insecticidal toxins, T3SS components, and proteins required for ethanolamine use (eut operon) and cobalamin (vitamin B12) biosynthesis. The eut operon and the gene cluster for cobalamin biosynthesis are not present in the other Proteeae genomes analysed. Moreover, organisation of the 19 genes of the eut operon differs from that found in the other non-Proteeae enterobacterial genomes.ConclusionsThis is the first genome sequence of M. morganii, which is a clinically relevant pathogen. Comparative genome analysis revealed several pathogenicity-related genes and novel genes not found in the genomes of other members of Proteeae. Thus, the genome sequence of M. morganii provides important information concerning virulence and determinants of fitness in this pathogen.

Pathogenesis of Proteus mirabilis Infection

“…Notably, MrpJ paralogs are not restricted to P. mirabilis as they have been detected in fimbrial operons from related genera (264–266). Because fimbriae allow bacteria to adhere or form biofilms in specific environments, and thus respond to niche-specific signals, MrpJ paralogs have been proposed to orchestrate genetic programs that are beneficial to those environments (132, 267).…”

Proteus mirabilisand Urinary Tract Infections

“…Searches of the recently annotated urinary pathogen Providencia stuartii 25827 genome, available in GenBank, revealed that mrpJ paralogs are also frequently associated with fimbrial operons in that species. Likewise, thirteen mrpJ paralogs are encoded by Morganella morganii , although only two are associated with fimbrial operons (206). Thus far, mrpJ paralogs have been identified by BLAST homology searches (207) in at least 20 other bacterial species.…”

Giant condyloma acuminatum: report of surgical treatment and evolution of healing

“…At the same time in which the foam exerted its analgesic effect in the lesion, it helped in the control of the infection through the absorption of the exudate by capillarity and its retention in the air spaces of the structure (20) . We can conclude that the conduct adopted, considering the presence of infection in the wound, were appropriate, once it is a immunosuppressed patient, affected by an infection by enterobacteria about which the literature demonstrates high mortality rates (26) . The same way, we may observe the effectiveness of the polyurethane foam with sustained release of ibuprofen helping in the control of the pain, since in only five days of use, there was an important reduction of the score (from 10 to 5) considering that the pain was reported only during the handling for changing the dressings.…”

“…When present, it releases toxins and enzymes, activates matrices of metalloproteinases (MMPs) and plasminogen, degrading elastin and thus interfering negatively in the healing process of the wound (24,25) . Most patients affected by M. morganii respond well to the antimicrobial treatment; however, mortality rates are high (26) . In this case, the infection was controlled with systemic antimicrobial associated to the topical, recommended in the presence of signs of systemic infection.…”