title: Major Transcriptome Changes Accompany the Growth of Pseudomonas aeruginosa in Blood from Patients with Severe Thermal Injuries.
abstract: Pseudomonas aeruginosa is a Gram-negative opportunistic pathogen that causes serious infections in immunocompromised hosts including severely burned patients. After multiplying within the burn wound, P. aeruginosa translocate into the bloodstream causing bacterial sepsis frequently leading to organ dysfunction and septic shock. Although the pathogenesis of P. aeruginosa infection of thermally-injured wounds has been extensively analyzed, little is known regarding the ability of P. aeruginosa to adapt and survive within the blood of severely burned patients during systemic infection. To identify such adaptations, transcriptome analyses (RNA-seq) were conducted on P. aeruginosa strain PA14 that was grown in whole blood from a healthy volunteer or three severely burned patients. Compared with growth in blood from healthy volunteers, growth of PA14 in the blood from severely burned patients significantly altered the expression of 2596 genes, with expression of 1060 genes enhanced, while that of 1536 genes was reduced. Genes whose expression was significantly reduced included genes related to quorum sensing, quorum sensing-controlled virulence factors and transport of heme, phosphate, and phosphonate. Genes whose expression was significantly enhanced were related to the type III secretion system, the pyochelin iron-acquisition system, flagellum synthesis, and pyocyanin production. We confirmed changes in expression of many of these genes using qRT-PCR. Although severe burns altered the levels of different blood components in each patient, the growth of PA14 in their blood produced similar changes in the expression of each gene. These results suggest that, in response to changes in the blood of severely burned patients and as part of its survival strategy, P. aeruginosa enhances the expression of certain virulence genes and reduces the expression of others.
authors.affiliation: Department of Surgery, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: Cassandra
authors.initials: C
authors.lastname: Kruczek
authors.affiliation: Center for Biotechnology and Genomics, Texas Tech University, Lubbock, Texas, United States of America.
authors.forename: Kameswara Rao
authors.initials: KR
authors.lastname: Kottapalli
authors.affiliation: Department of Surgery, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: Sharmila
authors.initials: S
authors.lastname: Dissanaike
authors.affiliation: Department of Immunology and Molecular Microbiology, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: Nyaradzo
authors.initials: N
authors.lastname: Dzvova
authors.affiliation: Department of Surgery, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: John A
authors.initials: JA
authors.lastname: Griswold
authors.affiliation: Department of Immunology and Molecular Microbiology, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.|Department of Medical Education, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Colmer-Hamood
authors.affiliation: Department of Surgery, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.|Department of Immunology and Molecular Microbiology, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, United States of America.
authors.forename: Abdul N
authors.initials: AN
authors.lastname: Hamood
mesh_terms: D000328:Adult; D002056:Burns / Q000097:blood / Q000150:complications* / Q000382:microbiology*; D015964:Gene Expression Regulation, Bacterial; D006801:Humans; D007501:Iron / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011552:Pseudomonas Infections / Q000097:blood / Q000150:complications* / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000235:genetics* / Q000254:growth & development* / Q000502:physiology; D053038:Quorum Sensing; D059467:Transcriptome; D000069296:Type III Secretion Systems / Q000235:genetics
chemical_list: D000069296:Type III Secretion Systems; D007501:Iron