Microbial Haemoglobins: Proteins at the Crossroads of Oxygen and Nitric Oxide Metabolism

  • Robert K. Poole
Part of the Protein Reviews book series (PRON, volume 9)


The globins of microorganisms were ignored for many decades after their discovery by Warburg in the 1930s and rediscovery by Keilin in the 1950s. Three classes of microbial globin are now recognised, all having features of the classical globin protein fold. The first is typified by the myoglobin-like protein, Vgb, from the bacterium Vitreoscilla, and by the Cgb protein of Campylobacter jejuni. Second, the truncated globins, widely distributed in bacteria, microbial eukaryotes and plants, are characterised by a two-over-two helical structure while retaining the essential features of the globin superfamily. The third and best understood class are the flavohaemoglobins, possessing an additional domain with binding sites for FAD and NAD(P)H. Flavohaemoglobins have no known physiological role in oxygen metabolism but undoubtedly confer protection from NO, as do some, but not all, of the myoglobin-like and truncated microbial globins. This chapter honours the contributions of Beatrice and Jonathan Wittenberg to globin research, specifically their work on bacterial truncated globins and their thoughtful consideration of the role of the bacterial myoglobin-like proteins. The focus of the chapter is on recent and current work from the Poole laboratory, with reference to earlier studies by the Wittenbergs. We have investigated all three classes of bacterial globins and used physiological and genetic methods to yield insights into globin function and reveal new roles for these old proteins in pathogenicity.


Nitric Oxide Nitric Oxide Reactive Nitrogen Species Nitrosative Stress Yersinia Pestis 


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Copyright information

© Springer-Verlag Italia 2008

Authors and Affiliations

  • Robert K. Poole
    • 1
  1. 1.Department of Molecular Biology and BiotechnologyThe University of SheffieldSheffieldUK

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