Evolutionary diversification and characterization of the eubacterial gene family encoding DXR type II, an alternative isoprenoid biosynthetic enzyme

Table 2 Analysis of functional divergence

Functional divergence	Families	Coefficient θ ± SE	Critical amino acid sites (Q_k > 0.7; *, Q_k > 0.95)
Type I	DXR-II vs DLO1	θ₁ = 0.277 ± 0.045 (LRT = 83.233; p = 7.292E-20 )	35, 46, 118, 121, 146, 161, 176, 198, 205, 218, 229, 234, 237, 247, 265, 282, 291, 297, 310, 340, 342, 351, 353, 376, 404, 410, 422, 424, 429
	DXR-II vs DLO2	θ₁ = 0.253 ± 0.043 (LRT = 114.991; p = 7.907E-27 )	35, 47, 64, 122, 128, 133, 197, 202, 205, 210, 239, 248, 250, 253, 258, 260, 282, 291, 296, 305, 310*, 311, 314, 320, 324, 330, 346, 351, 359, 383, 410, 413, 428, 432
Type II	DXR-II vs DLO1	θ₂ = −0.998 ± 0.487
	DXR-II vs DLO2	θ₂ = −1.115 ± 0.575

p = posterior probability values; SE Standard Error. LRT and resulting p-values are shown in parentheses. Critical amino acid sites detected as related to functional divergence with Q_k > 70% (*, Q_k > 95%) are listed. Seven sites predicted as related to functional divergence of DXR-II from both families DLO1 and DLO2 are indicated in bold. Numbering refers to Brucella melitensis biovar abortus 2308 DXR-II protein sequence.

ISSN: 2730-7182