Multiple orphan histidine kinases interact directly with Spo0A to control the initiation of endospore formation in Clostridium acetobutylicum

Abstract

The phosphorylated Spo0A transcription factor controls the initiation of endospore formation in Clostridium acetobutylicum, but genes encoding key phosphorelay components, Spo0F and Spo0B, are missing in the genome. We hypothesized that the five orphan histidine kinases of C. acetobutylicum interact directly with Spo0A to control its phosphorylation state. Sequential targeted gene disruption and gene expression profiling provided evidence for two pathways for Spo0A activation, one dependent on a histidine kinase encoded by cac0323, the other on both histidine kinases encoded by cac0903 and cac3319. Purified Cac0903 and Cac3319 kinases autophosphorylated and transferred phosphoryl groups to Spo0A in vitro, confirming their role in Spo0A activation in vivo. A cac0437 mutant hyper-sporulated, suggesting that Cac0437 is a modulator that prevents sporulation and maintains cellular Spo0A~P homeostasis during growth. Accordingly, Cac0437 has apparently lost the ability to autophosphorylate in vitro; instead it catalyses the ATP-dependent dephosphorylation of Spo0A~P releasing inorganic phosphate. Direct phosphorylation of Spo0A by histidine kinases and dephosphorylation by kinase-like proteins may be a common feature of the clostridia that may represent the ancestral state before the great oxygen event some 2.4 billion years ago, after which additional phosphorelay proteins were recruited in the evolutionary lineage that led to the bacilli.

ClosTron-Mediated Engineering of Clostridium

“…By way of example, it has been used to establish the role of bacterial factors (toxins, flagella and adhesins) in infection, 23,[26][27][28][29] to garner a greater understanding of the role and activities of enzymes in primary metabolism, [30][31][32][33] to begin to elucidate mechanistic details of the developmental process of spore formation/ germination 21,34,35 and provide fundamental information on regulatory processes important in virulence factor and metabolite production. [36][37][38][39] Its availability has provided the research community with a sequence of the re-targeted region used to generate the insertion should be given.…”

Esporas de Clostridium difficile y su relevancia en la persistencia y transmisión de la infección

“…El inicio del ciclo de esporulación comienza cuando quinasas histidinas huérfanas detectan estímulos ambientales y comienzan a fosforilar al regulador maestro de la esporulación, Spo0A 31,32 . El genoma secuenciado de C. difficile codifica cinco quinasas histidinas huérfanas (CD1352, CD1492, CD1579, CD1949 y CD2492) 33 .…”

A Life inBacillus subtilisSignal Transduction

“…Direct phosphorylation of Spo0A by histidine kinases and dephosphorylation by kinase-like proteins appear to be common features of the anaerobic clostridia. We speculated that this may represent the ancestral state before the great oxygen event some 2.4 billion years ago, after which additional phosphorelay proteins were recruited in the evolutionary lineage that led to the aerobic bacilli (75).…”