Reclassification of Clostridium cocleatum, Clostridium ramosum, Clostridium spiroforme and Clostridium saccharogumia as Thomasclavelia cocleata gen. nov., comb. nov., Thomasclavelia ramosa comb. nov., gen. nov., Thomasclavelia spiroformis comb. nov. and Thomasclavelia saccharogumia comb. nov

Abstract

The genus Clostridium is phenotypically and genotypically diverse, with many species phylogenetically located outside Clostridium sensu stricto. One such group consists of the species Clostridium cocleatum, Clostridium ramosum, Clostridium spiroforme and Clostridium saccharogumia (formally clostridial rRNA cluster XVIII) []. Sequencing of the 16S rRNA and, more recently, the results of genomic analyses have demonstrated that these species represent a coherent cluster separated from other closely related genera located in the family Coprobacillaceae within the order Erysipelotrichales []. In addition to phenotypic, phylogenetic and genomic comparisons, chemotaxonomic features were consistent between all four species, the predominant fatty acids were C16 : 0 and C18 : 1ω9c, while glucose and ribose were the whole cell sugars present in the cell walls. Furthermore, he results of peptidoglycan analysis indicated that meso-2,6-diaminopimelic acid was present as the diagnostic diamino acid in all four species. Biochemical profiles were also concordant with them being closely related species. Therefore, on the basis of phylogenetic, genomic, phenotypic and chemotaxonomic information, a novel genus, Thomasclavelia gen. nov., is proposed. It is suggested that Clostridium cocleatum, Clostridium ramosum, Clostridium spiroforme and Clostridium saccharogumia be transferred to this genus as Thomasclavelia cocleata comb. nov., Thomasclavelia ramosa comb. nov., Thomasclavelia saccharogumia comb. nov. and Thomasclavelia spiroformis comb. nov. The type species of the genus is Thomasclavelia ramosa CCUG 24038T (=ATCC 25582T=DSM 1402T).

Identification and distribution of new candidate T6SS effectors encoded in Salmonella Pathogenicity Island 6

“…Of note, this motif is also present in the T6SS antibacterial effector SED_RS06335 with putative peptidoglycan hydrolase activity encoded in SPI-19 of Salmonella Dublin CT_02021853 ( Amaya et al, 2022 ). The last candidate effector targeting the peptidoglycan identified in our study harbors the Peptidase_M64 protein domain that is also present in the IgA proteinase of Clostridium ramosum ( Kosowska et al, 2002 ), recently reclassified as Thomasclavelia ramosa ( Lawson et al, 2023 ). The putative immunity proteins of Reprolysin_4 and Peptidase_M64 have a signal peptide and a transmembrane domain, respectively.…”

Dextran sodium sulfate-induced colitis alters the proportion and composition of replicating gut bacteria

“…Despite a limited number of studies noting the contrary 99,[114][115][116] , these results are in accordance with the behaviour of Erysipelatoclostridium reported in prior studies during intestinal disturbance. Indeed, this genus and one of its species, namely Clostridium ramosum (also known as E. ramosum or Thomasclavelia ramosum), [117][118][119] have been associated with intestinal inflammation or injury in humans, 46,48,73,[120][121][122][123][124][125][126][127] increasing in abundance in mouse models of colitis [71][72][73][74][75][76][77][78][79][80][81][82] and infection 128 , and being positively correlated with fecal water content (i.e., diarrhea), a common colitis symptom 2,[22][23][24]129,130 . The high replication activity of Erysipelatoclostridium we report demonstrates that it is a particularly active taxon during colitis, resulting in a possibly outsized impact on the microbial environment and the host.…”

“…Despite a limited number of studies noting the contrary 99,[114][115][116] , these results are in accordance with the behaviour of Erysipelatoclostridium reported in prior studies during intestinal disturbance. Indeed, this genus and one of its species, namely Clostridium ramosum (also known as E. ramosum or Thomasclavelia ramosum), [117][118][119] have been associated…”

Clostridium tanneri sp. nov., isolated from the faecal material of an alpaca

“…In this study, an in-silico approach was used to investigate glycerophospholipid metabolism, the production of polar lipids was performed using the Kyoto Encyclopaedia of Gene and Genomes (KEGG) database [31]. An in-silico approach is now encouraged and routinely utilised for polar lipid profiling [32][33][34][35][36], and along with biochemical traits, these methods are now routinely used for species descriptions [37][38][39]. The results (Fig.…”