HAs sample on the other hand showed sporadic distribution of these agglomerates.
As reported above in rural China, the transmission pattern of drug-resistant TB was sporadic distribution and in small groups.
Alternatively, there may have been independent gene losses among cyanobacteria leading to the sporadic distribution of these sequences among the different lineages in our trees.
The sporadic distribution most likely results from horizontal gene transfer and strongly supports the endosymbiosis theory; the acquisition of the photosynthesis system in red algae from endosymbiotic cyanobacteria.
Gene loss alone, although it clearly occurs as exemplified by a residual methyltransferase in the nkd group, cannot account for the observed sporadic distribution.
Lateral gene transfer (LGT) and gene deletions are probable explanations for the sporadic distribution of saxitoxin producers among the different cyanobacterial species and across kingdoms [22], [27], [30].
The monophyletic grouping of the vlm gene cluster within the Streptomyces species is highly suggestive of inheritance from a common ancestry by VT rather than by HGT, which would typically result in a more sporadic distribution throughout the trees, amongst less highly related strains [29].
This emphasises the extremely sporadic distribution of inteins.
