Hunting across the M. xanthus DK1622 genome, in addition they identified frequent acquisition of metabolic genes by HGT, like a number of elements in the electron transport chain, reminiscent of the observations of Thomas et al. [17] for a. dehalogenans 2CP-C. Other examples of myxobacterial genes gained by HGT include things like those encoding sterol biosynthesis, an unusual phenomenon in bacteria, which myxobacteria probably acquired from eukaryotes [87]. Other studies have investigated the origin of genes which appear to possess arisen de novo inside myxobacterial evolution. The Pxr non-coding RNA which regulates fruiting physique formation seems to have evolved within the Cystobacterineae sub-order (now order Myxococcales), when the devI regulator of fruiting appears to become an incredibly current innovation inside M. xanthus [88,89]. Sequence analysis of 120 strains isolated from six fruiting bodies has shown that genomic changes are concentrated in `selection hot-spots’ as well as characterised the price of endemic diversification [32]. Luciano et al. [90] utilized a phylogenomic approach to characterise the evolution of candidate genes potentially involved in gliding motility. Employing evolutionary and syntenybased arguments they identified 3 genetic clusters encoding basal motility machinery. Their outcomes also recommended a model for the evolution of gliding motility wherein a core set of ancestral genes of unknown function subsequently recruited added functional modules [90]. A equivalent mode of evolution has also been recommended for the type IV pili-based motility systems of myxobacteria [91]. It is also worth noting right here an intriguing hypothesis regarding myxobacterial evolution, which suggests that an ancestral myxobacterium might have evolved into a nonmyxobacterium. The syntrophy hypothesis proposes that the eukaryotic prevalent ancestorMicroorganisms 2021, 9,16 ofwas the result of a tripartite symbiosis involving a myxobacterium-like deltaproteobacterium, which became the eukaryotic cytoplasm [92]. The hypothesis suggests the involvement of a myxobacterial-like organism on account of many functions of myxobacterial biology that are uncommon for bacteria, but frequent to eukaryotes, including (among numerous examples) defensins, eukaryotic-like Ser/Thr CD40 Activator Source kinases and enhanceosomes [58,93,94]. 3. Myxobacterial Post-Genomics The availability of a genome sequence is really a pre-requisite for several `omics technologies, specifically transcriptome and proteome analyses. The widespread application of such approaches to myxobacteria has led to the generation of massive numbers of `omics datasets, albeit mostly for M. xanthus. Increasingly, `omics research and other post-genomic approaches are supplying holistic insights into myxobacterial taxonomy, evolution and molecular biology. 3.1. Molecular Genetics The availability of a genome sequence can inform us about the function and origin of its constituent genes through H2 Receptor Modulator Biological Activity comparative genomics analyses and it makes it possible for the directed study of person genes or sets of gene in that genome (e.g., [957]. The roles of genes could be inferred if they share homology with genes of known function in other organisms, but comparative genomics also makes attainable the identification of candidate genes with no obvious functional relationship using the function, including those encoding hypothetical proteins [98]. For example, Luciano et al. [90] created functional predictions of gliding motility genes utilizing synteny-based arguments, when Sutton et al. [38] correlated gene presence/absence
