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The interaction of Yersinia pestis with erythrocytes
V A Feodorova1, Z L Devdariani1
1Laboratory of Hybridomas, Russia State Antiplague Research Institute 'Microbe', Saratov, Russia.
Abstract:
Human and murine erythrocytes (RBC) were invaded by Yersinia pestis in vivo and in vitro during a short period and were probably used as an essential source of iron and porphyrin for survival, effective gross multiplication and rapid spread of these bacteria in the bloodstream of mammals. Both iron and porphyrin were extracted by Y. pestis from the RBC through oxidase-catalase activity which produced oxidation of the RBC glucose with generation of H2O2 in large concentration leading to oxidative transformation of haemoglobin into haemin. Furthermore, some mainly chromosomally encoded effector proteins were implicated in this process because all were synthesised by Y. pestis grown in media simulating the intracellular conditions of mammalian RBC. Damaged RBC lost the ability to transport O2 in the mammalian organism. As a result, significant oxygen deficiency developed in host tissues providing specific clinical disease features of plague which are similar to characteristic symptoms of poisoning with haemotoxic substances when the transformation of the haemoglobin Fe2+ to Fe3+ occurs.
Insights
Yersinia pestis invades red blood cells (RBCs) for iron and porphyrin, essential for bacterial survival and spread. This process damages RBCs, causing oxygen deficiency and plague symptoms in mammals.
Area of Science:
- Microbiology
- Pathogenesis
- Hematology
Background:
- Yersinia pestis, the causative agent of plague, invades mammalian erythrocytes (red blood cells).
- Erythrocytes are a potential source of essential nutrients like iron and porphyrin for bacterial survival and proliferation.
- The mechanisms by which Y. pestis interacts with and utilizes components from erythrocytes are not fully elucidated.
Purpose of the Study:
- To investigate the role of erythrocytes as a nutrient source for Yersinia pestis.
- To elucidate the mechanisms of iron and porphyrin extraction from erythrocytes by Y. pestis.
- To understand the impact of Y. pestis invasion on erythrocyte function and host oxygen transport.
Main Methods:
- In vitro and in vivo invasion assays using human and murine erythrocytes.
- Analysis of bacterial enzyme activity (oxidase-catalase) involved in nutrient extraction.
- Cultivation of Y. pestis in simulated intracellular media to identify relevant effector proteins.
- Assessment of erythrocyte oxygen-carrying capacity post-invasion.
Main Results:
- Yersinia pestis invades erythrocytes, utilizing them as a source of iron and porphyrin for multiplication and spread.
- Bacterial oxidase-catalase activity facilitates iron and porphyrin extraction by oxidizing erythrocyte glucose and generating hydrogen peroxide.
- Effector proteins, synthesized under simulated intracellular conditions, are involved in this nutrient acquisition process.
- Damaged erythrocytes exhibit impaired oxygen transport, leading to tissue hypoxia and plague-like symptoms.
Conclusions:
- Yersinia pestis effectively exploits erythrocytes for essential nutrients, contributing to its pathogenesis.
- The interaction between Y. pestis and erythrocytes leads to functional impairment of red blood cells, impacting host oxygenation.
- Understanding this interaction provides insights into the clinical manifestations of plague and potential therapeutic targets.