Figure 3 Respiratory nitrate reduction pathway is specifically conserved in the Apibacter group, which is also possessed bySnodgrassella . A. Schematic diagram shows that the respiration nitrate reduction pathway together with molybdate cofactor synthesis are conserved accoss the Apibacter group (pink arrows), and nitrite detoxification (grey arrows) is absent in the Apibacter group but possessed by genomes in Clade C/E (genes distribution are provided in Dataset S5). B. Genomic regions of type strains of Apibacter fromA. cerana , bumble bee and A. dorsata encodes genes involved in respiratory nitrate reduction. Vertical grey blocks connect homologous genes among type strains, with numbers representing the percentage of sequence similarities. Genes in pink encodes nitrate reductase and transporter. Genes in blue encodes molybdate cofactor synthesis. Genes in grey are hypothetical genes or genes that are not directly related.