Mobile genetic element proliferation and gene inactivation impact over the genome structure and metabolic capabilities of Sodalis glossinidius, the secondary endosymbiont of tsetse flies

Table 1 Structural and evolutionary characteristics of the 5 main groups of IS elements characterized in the genome of S. glossinidiu s.

		ISSgl1	ISSgl2	ISSgl3	ISSgl4	ISSgl5
IS family		IS5	IS110	IS256	IS110	ISNCY
Structural features
	Consensus sequence length (bp)	1052	1175	1247	1210	939
	GC content (%)	49.8	49.7	51	48.7	52.7
	Number of open reading frames	1	1	1	1	1
	Inverted repeats (bp)	17	11	34	10	n.d. ^(c)
	Direct repeats derived from transposition (bp)	9	n.d. ^(d)	9	n.d. ^(d)	n.d. ^(d)
Complete copies ^(a)		47	9	7	7	4
Partial copies ^(b)		16	9	12	2	9
IS with functional transposase genes		10	4	0	0	0
Pseudogenes by IS insertion		10	2	2	3	0
p-distance (number of nucleotide differences/total length)
	Minimum	0.0	0.0024	0.0062	0.0048	0.1097
	Maximum	0.066	0.0268	0.0756	0.0240	0.3935
	Mean	0.02	0.0162	0.0287	0.0131	0.2388
Total length (nt) ^(e)		52130	15328	16915	9375	11411

^a Complete copies are those that present inverted repeats at both ends of the transposase gene.
^b Partial copies correspond to fragments of the putative IS element.
^c No inverted repeats were detected in ISSgl5
^d No direct repeats were detected in ISSgl2, ISSgl4, and ISSgl5 (n.d.).
^e Sum of the length of all corresponding complete and partial IS elements.

ISSN: 1471-2164