ArticleInfection and immunity1995
pH and calcium dependence of hemolysis due to Rickettsia prowazekii: comparison with phospholipase activity.
Article in Infection and immunity, 1995. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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Who cites it
9 citing papers in PubMed, 29 citations in OpenAlex.
- TlyC, a conserved hemolysin inMicrobiology spectrum · 2025Article
- Rickettsia-host interaction: strategies of intracytosolic host colonization.Pathogens and disease · 2021Review
- Secretome of obligate intracellular Rickettsia.FEMS microbiology reviews · 2015Review
- Rickettsia typhi possesses phospholipase A2 enzymes that are involved in infection of host cells.PLoS pathogens · 2013Article
- The Rickettsia prowazekii ExoU homologue possesses phospholipase A1 (PLA1), PLA2, and lyso-PLA2 activities and can function in the absence of any eukaryotic cofactors in vitro.Journal of bacteriology · 2011Article
- Functional characterization of a phospholipase A(2) homolog from Rickettsia typhi.Journal of bacteriology · 2010Article
- Limited transcriptional responses of Rickettsia rickettsii exposed to environmental stimuli.PloS one · 2009Article
- Identification and molecular analysis of the gene encoding Rickettsia typhi hemolysin.Infection and immunity · 1999Article
- Molecular characterization of pldA, the structural gene for a phospholipase A from Campylobacter coli, and its contribution to cell-associated hemolysis.Infection and immunity · 1997Article
Corrections and comments
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Authors and funding
4 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Rickettsia prowazekii invades nucleated cells through phagocytosis and subsequently proliferates in the cytoplasm of the host cell. Hemolysis and a phospholipase A2 (PLA2) activity at neutral pHs have previously been reported; even though the phagosomal environment is most likely acidic. We here show that R. prowazekii and R. typhi also lyse erythrocytes at mildly acidic pHs, compatible with an early phagosomal compartment. For R. prowazekii, hemolysis at an acidic pH but not a neutral pH is enhanced by Ca2+, raising the possibility that more than one membranolytic factor may be produced by the rickettsiae. The rickettsiae alone display PLA2 activity, implying that the enzyme is of bacterial rather than erythrocyte or host cell origin. Moreover, the PLA2 activity requires divalent cations (Ca2+ or Mg2+), and, as with many extracellular PLA2s from other species, it has a preference for acidic over neutral phospholipids. The pH dependence of PLA2 is similar to that of the hemolysis without Ca2+, but in the presence of the hemolysis buffers (which contain Mg2+), there is no calcium-induced enhancement at acidic pHs. Thus, these rickettsiae are endowed with a membranolytic activity that could contribute to the escape of the bacteria from early phagosomal compartments, and it is likely that multiple toxins may be used for membrane lysis.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.