| genetic diversity of leptotrichia and description of leptotrichia goodfellowii sp. nov., leptotrichia hofstadii sp. nov., leptotrichia shahii sp. nov. and leptotrichia wadei sp. nov. | sixty strains of gram-negative, anaerobic, rod-shaped bacteria from human sources initially assigned to leptotrichia buccalis (n=58) and 'leptotrichia pseudobuccalis' (n=2) have been subjected to polyphasic taxonomy. full-length 16s rdna sequencing, dna-dna hybridization, rapd, sds-page of whole-cell proteins, cellular fatty acid analysis and enzymic/biochemical tests supported the establishment of four novel leptotrichia species from this collection, leptotrichia goodfellowii sp. nov. (type str ... | 2004 | 15023979 |
| two distant catalytic sites are responsible for c2c2 rnase activities. | c2c2, the effector of type vi crispr-cas systems, has two rnase activities-one for cutting its rna target and the other for processing the crispr rna (crrna). here, we report the structures of leptotrichia shahii c2c2 in its crrna-free and crrna-bound states. while c2c2 has a bilobed structure reminiscent of all other class 2 effectors, it also exhibits different structural characteristics. it contains the rec lobe with a helical-1 domain and the nuc lobe with two hepn domains. the two rnase cat ... | 2017 | 28086085 |
| c2c2 is a single-component programmable rna-guided rna-targeting crispr effector. | the clustered regularly interspaced short palindromic repeat (crispr)-crispr-associated genes (cas) adaptive immune system defends microbes against foreign genetic elements via dna or rna-dna interference. we characterize the class 2 type vi crispr-cas effector c2c2 and demonstrate its rna-guided ribonuclease function. c2c2 from the bacterium leptotrichia shahii provides interference against rna phage. in vitro biochemical analysis shows that c2c2 is guided by a single crispr rna and can be prog ... | 2016 | 27256883 |