Discovery of Catalases in Members of the Chlamydiales Order

Abstract

Catalase is an important virulence factor for survival in macrophages and other phagocytic cells. In Chlamydiaceae, no catalase had been described so far. With the sequencing and annotation of the full genomes of Chlamydia-related bacteria, the presence of different catalase-encoding genes has been documented. However, their distribution in the Chlamydiales order and the functionality of these catalases remain unknown. Phylogeny of chlamydial catalases was inferred using MrBayes, maximum likelihood, and maximum parsimony algorithms, allowing the description of three clade 3 and two clade 2 catalases. Only monofunctional catalases were found (no catalase-peroxidase or Mn-catalase). All presented a conserved catalytic domain and tertiary structure. Enzymatic activity of cloned chlamydial catalases was assessed by measuring hydrogen peroxide degradation. The catalases are enzymatically active with different efficiencies. The catalase of Parachlamydia acanthamoebae is the least efficient of all (its catalytic activity was 2 logs lower than that of Pseudomonas aeruginosa). Based on the phylogenetic analysis, we hypothesize that an ancestral class 2 catalase probably was present in the common ancestor of all current Chlamydiales but was retained only in Criblamydia sequanensis and Neochlamydia hartmannellae. The catalases of class 3, present in Estrella lausannensis and Parachlamydia acanthamoebae, probably were acquired by lateral gene transfer from Rhizobiales, whereas for Waddlia chondrophila they likely originated from Legionellales or Actinomycetales. The acquisition of catalases on several occasions in the Chlamydiales suggests the importance of this enzyme for the bacteria in their host environment.

Importance of amoebae as a tool to isolate amoeba‐resisting microorganisms and for their ecology and evolution: the Chlamydia paradigm

“…A recent work by Rusconi and Greub (), demonstrated that, contrarily to Chlamydiaceae , several Chlamydia ‐related bacteria possess a functional catalase, an enzyme likely important for survival in phagocytic cells such as macrophages. The total absence of this enzyme in Chlamydiaceae might be one reason why the macrophage and amoebal environments are hostile to these bacteria (Wirz et al ., ; Beagley et al ., ).…”

“…It can detect five DNA copies of any member of the Chlamydiales order, exhibits a high specificity for bacteria of this order and does not amplify DNA of any other bacterial clade (Lienard et al ., 2011b). This new PCR may fill the gap generally left when using conventional eubacterial PCR. Because of particular features of their extracellular membrane (Rusconi and Greub, ; Rusconi et al ., ), chlamydial elementary bodies are highly resistant to classical bacterial lysis protocols thus hampering DNA extraction (Croxatto et al ., ). An alternate extraction protocol has thus been set up (Croxatto et al ., ) that includes a 2 h proteinase K digestion step ensuring complete bacterial membrane lysis and consequently efficient DNA extraction. Chlamydiales bacteria are obligate intracellular organisms strictly dependent of an eukaryotic host for multiplication.…”

“…Because of particular features of their extracellular membrane (Rusconi and Greub, ; Rusconi et al ., ), chlamydial elementary bodies are highly resistant to classical bacterial lysis protocols thus hampering DNA extraction (Croxatto et al ., ). An alternate extraction protocol has thus been set up (Croxatto et al ., ) that includes a 2 h proteinase K digestion step ensuring complete bacterial membrane lysis and consequently efficient DNA extraction.…”

Sequencing and characterizing the genome of Estrella lausannensis as an undergraduate project: training students and biological insights

“…The bacterium was also shown to grow in two fish cell lines but could not induce cell lysis (Kebbi-Beghdadi et al, 2011 ). Survival and growth in macrophages and other professional phagocytes is made possible by the presence of a class 3 catalase that degrade reactive oxygen species (Rusconi and Greub, 2013 ).…”

Simkania negevensis, an insight into the biology and clinical importance of a novel member of the Chlamydiales order

“…¶ ¶Putative Pmp encoded in the genome, but not isolated at the membrane. § § (Collingro et al, 2011;Rusconi & Greub, 2013). jjjj (Bertelli et al, 2010;Carlson et al, 2006;Collingro et al, 2011;Horn et al, 2004;Knab et al, 2011;Omsland et al, 2014).…”