Table 2. Genes of the secondary metabolism in leaf nodule symbionts.

Putative product	Ca. B. kirkii	Ca. B. punctata	Ca. B. pumila	Ca. B. humilis	Ca. B. schumanniana	Ca. B. verschuerenii	Ca. B. umbellata	Ca. B. brachyanthoides
2-epi-5-epi-valiolone synthase (Bkir_c149_4879)								Ψ
N-acetylmannosamine kinase (Bkir_c149_4878)
Aminosugar transaminase (Bkir_c149_4877)				Ψ
Glycoside hydrolase (Bkir_c149_4876)
Sugar dehydrogenase (Bkir_c149_4875)
HAD family hydrolase (Bkir_c149_4874)
Sugar phosphate isomerase (Bkir_c149_4873)				Ψ
Acetyltransferase, GNAT family (Bkir_c149_4873)
Dioxygenase (Bkir_c48_3583)
Methyltransferase (Bkir_c48_3584)
C7-cyclitol-7-kinase (Bkir_c48_3591)
3-dehydroquinate synthase (Bkir_c48_3593)
dTDP-4-dehydrorhamnose reductase (Bkir_c48_3594)
NUDIX family hydrolase (Bkir_c48_3606)
Kirkamide	+	+	+	+	−	+	−	−

Genes of Ca. B. kirkii are used as a reference. Functional homologues are highlighted in grey and pseudogenes indicated by Ψ. Conserved genes are shown in bold. Detection of kirkamide in crude leaf extracts is indicated by a + symbol. A − symbol indicates kirkamide concentrations below detection levels (see Materials and Methods).