Many insects harbor bacterial endosymbionts that supply essential nutrients and enable their hosts to thrive on a nutritionally unbalanced diet. Comparisons of the genomes of endosymbionts and their insect hosts have revealed multiple cases of mutually-dependent metabolic pathways that require enzymes encoded in 2 genomes. Complementation of metabolic reactions at the pathway level has been described for hosts feeding on unbalanced diets, such as plant sap. However, the level of collaboration between symbionts and hosts that feed on more variable diets is largely unknown. In this study, we investigated amino acid and vitamin/cofactor biosynthetic pathways in Blattodea, which comprises cockroaches and termites, and their obligate endosymbiont Blattabacterium cuenoti (hereafter Blattabacterium). In contrast to other obligate symbiotic systems, we found no clear evidence of "collaborative pathways" for amino acid biosynthesis in the genomes of these taxa, with the exception of collaborative arginine biosynthesis in 2 taxa, Cryptocercus punctulatus and Mastotermes darwiniensis. Nevertheless, we found that several gaps specific to Blattabacterium in the folate biosynthetic pathway are likely to be complemented by their host. Comparisons with other insects revealed that, with the exception of the arginine biosynthetic pathway, collaborative pathways for essential amino acids are only observed in phloem-sap feeders. These results suggest that the host diet is an important driving factor of metabolic pathway evolution in obligate symbiotic systems. IMPORTANCE The long-term coevolution between insects and their obligate endosymbionts is accompanied by increasing levels of genome integration, sometimes to the point that metabolic pathways require enzymes encoded in two genomes, which we refer to as "collaborative pathways". To date, collaborative pathways have only been reported from sap-feeding insects. Here, we examined metabolic interactions between cockroaches, a group of detritivorous insects, and their obligate endosymbiont, Blattabacterium, and only found evidence of collaborative pathways for arginine biosynthesis. The rarity of collaborative pathways in cockroaches and Blattabacterium contrasts with their prevalence in insect hosts feeding on phloem-sap. Our results suggest that host diet is a factor affecting metabolic integration in obligate symbiotic systems.

Faculty of Tropical AgriSciences Czech University of Life Sciences Kamýcká Prague Czech Republic

Okinawa Institute of Science and Technologygrid 250464 1 Graduate University Okinawa Japan

RIKEN Bioresource Research Centre Tsukuba Japan

School of Life and Environmental Sciences University of Sydney Sydney New South Wales Australia

School of Life Science and Technology Tokyo Institute of Technology Tokyo Japan

Tropical Biosphere Research Center University of the Ryukyusgrid 267625 2 Okinawa Japan

Zobrazit více v PubMed

Moran NA, McCutcheon JP, Nakabachi A. 2008. Genomics and evolution of heritable bacterial symbionts. Annu Rev Genet 42:165–190. doi:10.1146/annurev.genet.41.110306.130119. PubMed DOI

Moya A, Peretó J, Gil R, Latorre A. 2008. Learning how to live together: genomic insights into prokaryote–animal symbioses. Nat Rev Genet 9:218–229. doi:10.1038/nrg2319. PubMed DOI

Macdonald SJ, Lin GG, Russell CW, Thomas GH, Douglas AE. 2012. The central role of the host cell in symbiotic nitrogen metabolism. Proc Biol Sci 279:2965–2973. doi:10.1098/rspb.2012.0414. PubMed DOI PMC

Shigenobu S, Wilson ACC. 2011. Genomic revelations of a mutualism: the pea aphid and its obligate bacterial symbiont. Cell Mol Life Sci 68:1297–1309. doi:10.1007/s00018-011-0645-2. PubMed DOI PMC

Shigenobu S, Watanabe H, Hattori M, Sakaki Y, Ishikawa H. 2000. Genome sequence of the endocellular bacterial symbiont of aphids Buchnera sp. APS. Nature 407:81–86. doi:10.1038/35024074. PubMed DOI

The International Aphid Genomics Consortium. 2010. Genome sequence of the pea aphid Acyrthosiphon pisum. PLoS Biol 8:e1000313. doi:10.1371/journal.pbio.1000313. PubMed DOI PMC

Wilson ACC, Ashton PD, Calevro F, Charles H, Colella S, Febvay G, Jander G, Kushlan PF, Macdonald SJ, Schwartz JF, Thomas GH, Douglas AE. 2010. Genomic insight into the amino acid relations of the pea aphid, Acyrthosiphon pisum, with its symbiotic bacterium Buchnera aphidicola: Amino acid metabolism genes in the pea aphid symbiosis. Insect Mol Biol 19:249–258. doi:10.1111/j.1365-2583.2009.00942.x. PubMed DOI

Hansen AK, Moran NA. 2011. Aphid genome expression reveals host–symbiont cooperation in the production of amino acids. Proc Natl Acad Sci USA 108:2849–2854. doi:10.1073/pnas.1013465108. PubMed DOI PMC

Russell CW, Bouvaine S, Newell PD, Douglas AE. 2013. Shared metabolic pathways in a coevolved insect-bacterial symbiosis. Appl Environ Microbiol 79:6117–6123. doi:10.1128/AEM.01543-13. PubMed DOI PMC

Wilson ACC, Duncan RP. 2015. Signatures of host/symbiont genome coevolution in insect nutritional endosymbioses. Proc Natl Acad Sci USA 112:10255–10261. doi:10.1073/pnas.1423305112. PubMed DOI PMC

Husnik F, Nikoh N, Koga R, Ross L, Duncan RP, Fujie M, Tanaka M, Satoh N, Bachtrog D, Wilson ACC, von Dohlen CD, Fukatsu T, McCutcheon JP. 2013. Horizontal gene transfer from diverse bacteria to an insect genome enables a tripartite nested mealybug symbiosis. Cell 153:1567–1578. doi:10.1016/j.cell.2013.05.040. PubMed DOI

Sloan DB, Nakabachi A, Richards S, Qu J, Murali SC, Gibbs RA, Moran NA. 2014. Parallel histories of horizontal gene transfer facilitated extreme reduction of endosymbiont genomes in sap-feeding insects. Mol Biol Evol 31:857–871. doi:10.1093/molbev/msu004. PubMed DOI PMC

Hansen AK, Moran NA. 2014. The impact of microbial symbionts on host plant utilization by herbivorous insects. Mol Ecol 23:1473–1496. doi:10.1111/mec.12421. PubMed DOI

Gil R, Silva FJ, Zientz E, Delmotte F, Gonzalez-Candelas F, Latorre A, Rausell C, Kamerbeek J, Gadau J, Holldobler B, van Ham RCHJ, Gross R, Moya A. 2003. The genome sequence of Blochmannia floridanus: comparative analysis of reduced genomes. Proc Natl Acad Sci USA 100:9388–9393. doi:10.1073/pnas.1533499100. PubMed DOI PMC

Lo N, Tokuda G, Watanabe H, Rose H, Slaytor M, Maekawa K, Bandi C, Noda H. 2000. Evidence from multiple gene sequences indicates that termites evolved from wood-feeding cockroaches. Curr Biol 10:801–804. doi:10.1016/s0960-9822(00)00561-3. PubMed DOI

Bell WJ, Roth LM, Nalepa CA. 2007. Cockroaches: Ecology, Behavior, and Natural History. JHU Press, Charles Village Baltimore.

Lo N, Bandi C, Watanabe H, Nalepa C, Beninati T. 2003. Evidence for cocladogenesis between diverse Dictyopteran lineages and their intracellular endosymbionts. Mol Biol Evol 20:907–913. doi:10.1093/molbev/msg097. PubMed DOI

Bourguignon T, Tang Q, Ho SYW, Juna F, Wang Z, Arab DA, Cameron SL, Walker J, Rentz D, Evans TA, Lo N. 2018. Transoceanic dispersal and plate tectonics shaped global cockroach distributions: evidence from mitochondrial phylogenomics. Mol Biol Evol 35:970–983. doi:10.1093/molbev/msy013. PubMed DOI

Evangelista DA, Wipfler B, Béthoux O, Donath A, Fujita M, Kohli MK, Legendre F, Liu S, Machida R, Misof B, Peters RS, Podsiadlowski L, Rust J, Schuette K, Tollenaar W, Ware JL, Wappler T, Zhou X, Meusemann K, Simon S. 2019. An integrative phylogenomic approach illuminates the evolutionary history of cockroaches and termites (Blattodea). Proc Biol Sci 286:20182076. doi:10.1098/rspb.2018.2076. PubMed DOI PMC

Moran NA, Munson MA, Baumann P, Ishikawa H. 1993. A molecular clock in endosymbiotic bacteria is calibrated using the insect hosts. Proc R Soc Lond B Biol Sci 253:167–171. doi:10.1098/rspb.1993.0098. DOI

Cochran DG. 1985. Nitrogen excretion in cockroaches. Annu Rev Entomol 30:29–49. doi:10.1146/annurev.en.30.010185.000333. DOI

López-Sánchez MJ, Neef A, Peretó J, Patiño-Navarrete R, Pignatelli M, Latorre A, Moya A. 2009. Evolutionary convergence and nitrogen metabolism in Blattabacterium strain Bge, primary endosymbiont of the cockroach Blattella germanica. PLoS Genet 5:e1000721. doi:10.1371/journal.pgen.1000721. PubMed DOI PMC

Sabree ZL, Kambhampati S, Moran NA. 2009. Nitrogen recycling and nutritional provisioning by Blattabacterium, the cockroach endosymbiont. Proc Natl Acad Sci USA 106:19521–19526. doi:10.1073/pnas.0907504106. PubMed DOI PMC

de Crécy-Lagard V. 2014. Variations in metabolic pathways create challenges for automated metabolic reconstructions: Examples from the tetrahydrofolate synthesis pathway. Comput Struct Biotechnol J 10:41–50. doi:10.1016/j.csbj.2014.05.008. PubMed DOI PMC

Price MN, Zane GM, Kuehl JV, Melnyk RA, Wall JD, Deutschbauer AM, Arkin AP. 2018. Filling gaps in bacterial amino acid biosynthesis pathways with high-throughput genetics. PLoS Genet 14:e1007147. doi:10.1371/journal.pgen.1007147. PubMed DOI PMC

Reddy SRR, Campbell JW. 1977. Enzymic basis for the nutritional requirement of arginine in insects. Experientia 33:160–161. doi:10.1007/BF02124040. PubMed DOI

Yip SH-C, Matsumura I. 2013. Substrate ambiguous enzymes within the Escherichia coli proteome offer different evolutionary solutions to the same problem. Mol Biol Evol 30:2001–2012. doi:10.1093/molbev/mst105. PubMed DOI PMC

Sabree ZL, Huang CY, Arakawa G, Tokuda G, Lo N, Watanabe H, Moran NA. 2012. Genome shrinkage and loss of nutrient-providing potential in the obligate symbiont of the primitive termite Mastotermes darwiniensis. Appl Environ Microbiol 78:204–210. doi:10.1128/AEM.06540-11. PubMed DOI PMC

Kinjo Y, Bourguignon T, Tong KJ, Kuwahara H, Lim SJ, Yoon KB, Shigenobu S, Park YC, Nalepa CA, Hongoh Y, Ohkuma M, Lo N, Tokuda G. 2018. Parallel and gradual genome erosion in the Blattabacterium endosymbionts of Mastotermes darwiniensis and Cryptocercus wood roaches. Genome Biol Evol 10:1622–1630. doi:10.1093/gbe/evy110. PubMed DOI PMC

Neef A, Latorre A, Peretó J, Silva FJ, Pignatelli M, Moya A. 2011. Genome economization in the endosymbiont of the wood roach Cryptocercus punctulatus due to drastic loss of amino acid synthesis capabilities. Genome Biol Evol 3:1437–1448. doi:10.1093/gbe/evr118. PubMed DOI PMC

Kinjo Y, Lo N, Martín PV, Tokuda G, Pigolotti S, Bourguignon T. 2021. Enhanced mutation rate, relaxed selection, and the “domino effect” are associated with gene loss in Blattabacterium, a cockroach endosymbiont. Mol Biol Evol 38:3820–3831. doi:10.1093/molbev/msab159. PubMed DOI PMC

Klein CC, Alves JMP, Serrano MG, Buck GA, Vasconcelos ATR, Sagot M-F, Teixeira MMG, Camargo EP, Motta MCM. 2013. Biosynthesis of vitamins and cofactors in bacterium-harbouring Trypanosomatids depends on the symbiotic association as revealed by genomic analyses. PLoS One 8:e79786. doi:10.1371/journal.pone.0079786. PubMed DOI PMC

Luan J-B, Chen W, Hasegawa DK, Simmons AM, Wintermantel WM, Ling K-S, Fei Z, Liu S-S, Douglas AE. 2015. Metabolic coevolution in the bacterial symbiosis of whiteflies and related plant sap-feeding insects. Genome Biol Evol 7:2635–2647. doi:10.1093/gbe/evv170. PubMed DOI PMC

Kinjo Y, Saitoh S, Tokuda G. 2015. An efficient strategy developed for next-generation sequencing of endosymbiont genomes performed using crude DNA isolated from host tissues: A case study of Blattabacterium cuenoti inhabiting the fat bodies of cockroaches. Microbes Environ 30:208–220. doi:10.1264/jsme2.ME14153. PubMed DOI PMC

Huang CY, Sabree ZL, Moran NA. 2012. Genome sequence of Blattabacterium sp. strain BGIGA, endosymbiont of the Blaberus giganteus cockroach. J Bacteriol 194:4450–4451. doi:10.1128/JB.00789-12. PubMed DOI PMC

Patiño-Navarrete R, Moya A, Latorre A, Peretó J. 2013. Comparative genomics of Blattabacterium cuenoti: the frozen legacy of an ancient endosymbiont genome. Genome Biol Evol 5:351–361. doi:10.1093/gbe/evt011. PubMed DOI PMC

Williams LE, Wernegreen JJ. 2015. Genome evolution in an ancient bacteria-ant symbiosis: parallel gene loss among Blochmannia spanning the origin of the ant tribe Camponotini. PeerJ 3:e881. doi:10.7717/peerj.881. PubMed DOI PMC

Williams LE, Wernegreen JJ. 2013. Sequence context of indel mutations and their effect on protein evolution in a bacterial endosymbiont. Genome Biol Evol 5:599–605. doi:10.1093/gbe/evt033. PubMed DOI PMC

Degnan PH, Lazarus AB, Wernegreen JJ. 2005. Genome sequence of Blochmannia pennsylvanicus indicates parallel evolutionary trends among bacterial mutualists of insects. Genome Res 15:1023–1033. doi:10.1101/gr.3771305. PubMed DOI PMC

Williams LE, Wernegreen JJ. 2010. Unprecedented loss of ammonia assimilation capability in a urease-encoding bacterial mutualist. BMC Genomics 11:687. doi:10.1186/1471-2164-11-687. PubMed DOI PMC

Cassone BJ, Wenger JA, Michel AP. 2015. Whole genome sequence of the soybean aphid endosymbiont Buchnera aphidicola and genetic differentiation among biotype-specific strains. J Genomics 3:85–94. doi:10.7150/jgen.12975. PubMed DOI PMC

Pérez-Brocal V, Gil R, Ramos S, Lamelas A, Postigo M, Michelena JM, Silva FJ, Moya A, Latorre A. 2006. A small microbial genome: the end of a long symbiotic relationship? Science 314:312–313. doi:10.1126/science.1130441. PubMed DOI

van Ham RCHJ, Kamerbeek J, Palacios C, Rausell C, Abascal F, Bastolla U, Fernández JM, Jiménez L, Postigo M, Silva FJ, Tamames J, Viguera E, Latorre A, Valencia A, Morán F, Moya A. 2003. Reductive genome evolution in Buchnera aphidicola. Proc Natl Acad Sci USA 100:581–586. doi:10.1073/pnas.0235981100. PubMed DOI PMC

Chong RA, Park H, Moran NA. 2019. Genome evolution of the obligate endosymbiont Buchnera aphidicola. Mol Biol Evol 36:1481–1489. doi:10.1093/molbev/msz082. PubMed DOI

Degnan PH, Ochman H, Moran NA. 2011. Sequence conservation and functional constraint on intergenic spacers in reduced genomes of the obligate symbiont Buchnera. PLoS Genet 7:e1002252. doi:10.1371/journal.pgen.1002252. PubMed DOI PMC

Sloan DB, Moran NA. 2012. Genome reduction and co-evolution between the primary and secondary bacterial symbionts of psyllids. Mol Biol Evol 29:3781–3792. doi:10.1093/molbev/mss180. PubMed DOI PMC

Nakabachi A, Yamashita A, Toh H, Ishikawa H, Dunbar HE, Moran NA, Hattori M. 2006. The 160-kilobase genome of the Bacterial endosymbiont Carsonella. Science 314:267–267. doi:10.1126/science.1134196. PubMed DOI

Nakabachi A, Ueoka R, Oshima K, Teta R, Mangoni A, Gurgui M, Oldham NJ, van Echten-Deckert G, Okamura K, Yamamoto K, Inoue H, Ohkuma M, Hongoh Y, Miyagishima S, Hattori M, Piel J, Fukatsu T. 2013. Defensive bacteriome symbiont with a drastically reduced genome. Curr Biol 23:1478–1484. doi:10.1016/j.cub.2013.06.027. PubMed DOI

Sloan DB, Moran NA. 2012. Endosymbiotic bacteria as a source of carotenoids in whiteflies. Biol Lett 8:986–989. doi:10.1098/rsbl.2012.0664. PubMed DOI PMC

Santos-Garcia D, Farnier P-A, Beitia F, Zchori-Fein E, Vavre F, Mouton L, Moya A, Latorre A, Silva FJ. 2012. Complete genome sequence of “Candidatus Portiera aleyrodidarum” BT-QVLC, an obligate symbiont that supplies amino acids and carotenoids to Bemisia tabaci. J Bacteriol 194:6654–6655. doi:10.1128/JB.01793-12. PubMed DOI PMC

Chen W, Hasegawa DK, Kaur N, Kliot A, Pinheiro PV, Luan J, Stensmyr MC, Zheng Y, Liu W, Sun H, Xu Y, Luo Y, Kruse A, Yang X, Kontsedalov S, Lebedev G, Fisher TW, Nelson DR, Hunter WB, Brown JK, Jander G, Cilia M, Douglas AE, Ghanim M, Simmons AM, Wintermantel WM, Ling K-S, Fei Z. 2016. The draft genome of whitefly Bemisia tabaci MEAM1, a global crop pest, provides novel insights into virus transmission, host adaptation, and insecticide resistance. BMC Biol 14:110. doi:10.1186/s12915-016-0321-y. PubMed DOI PMC

Sloan DB, Moran NA. 2013. The evolution of genomic instability in the obligate endosymbionts of whiteflies. Genome Biol Evol 5:783–793. doi:10.1093/gbe/evt044. PubMed DOI PMC

McCutcheon JP, von Dohlen CD. 2011. An interdependent metabolic patchwork in the nested symbiosis of mealybugs. Curr Biol 21:1366–1372. doi:10.1016/j.cub.2011.06.051. PubMed DOI PMC

López-Madrigal S, Latorre A, Porcar M, Moya A, Gil R. 2011. Complete genome sequence of “Candidatus Tremblaya princeps” strain PCVAL, an intriguing translational machine below the living-cell status. J Bacteriol 193:5587–5588. doi:10.1128/JB.05749-11. PubMed DOI PMC

Sabree ZL, Huang CY, Okusu A, Moran NA, Normark BB. 2013. The nutrient supplying capabilities of Uzinura, an endosymbiont of armoured scale insects: Beneficial endosymbiont of armoured scale insects. Environ Microbiol 15:1988–1999. doi:10.1111/1462-2920.12058. PubMed DOI

Rosas-Pérez T, Rosenblueth M, Rincón-Rosales R, Mora J, Martínez-Romero E. 2014. Genome sequence of “Candidatus Walczuchella monophlebidarum” the flavobacterial endosymbiont of Llaveia axin axin (Hemiptera: Coccoidea: Monophlebidae). Genome Biol Evol 6:714–726. doi:10.1093/gbe/evu049. PubMed DOI PMC

Bennett GM, Moran NA. 2013. Small, smaller, smallest: the origins and evolution of ancient dual symbioses in a phloem-feeding insect. Genome Biol Evol 5:1675–1688. doi:10.1093/gbe/evt118. PubMed DOI PMC

Bennett GM, McCutcheon JP, MacDonald BR, Romanovicz D, Moran NA. 2014. Differential genome evolution between companion symbionts in an insect-bacterial symbiosis. mBio 5:e01697-14. doi:10.1128/mBio.01697-14. PubMed DOI PMC

Woyke T, Tighe D, Mavromatis K, Clum A, Copeland A, Schackwitz W, Lapidus A, Wu D, McCutcheon JP, McDonald BR, Moran NA, Bristow J, Cheng J-F. 2010. One bacterial cell, one complete genome. PLoS One 5:e10314. doi:10.1371/journal.pone.0010314. PubMed DOI PMC

McCutcheon JP, Moran NA. 2007. Parallel genomic evolution and metabolic interdependence in an ancient symbiosis. Proc Natl Acad Sci USA 104:19392–19397. doi:10.1073/pnas.0708855104. PubMed DOI PMC

Chang H-H, Cho S-T, Canale MC, Mugford ST, Lopes JRS, Hogenhout SA, Kuo C-H. 2015. Complete genome sequence of “Candidatus Sulcia muelleri” ML, an obligate nutritional symbiont of maize leafhopper (Dalbulus maidis). Genome Announc 3:e01483-14. doi:10.1128/genomeA.01483-14. PubMed DOI PMC

Koga R, Moran NA. 2014. Swapping symbionts in spittlebugs: evolutionary replacement of a reduced genome symbiont. ISME J 8:1237–1246. doi:10.1038/ismej.2013.235. PubMed DOI PMC

Bennett GM, Abbà S, Kube M, Marzachì C. 2016. Complete genome sequences of the obligate symbionts “Candidatus Sulcia muelleri” and “Ca. Nasuia deltocephalinicola” from the pestiferous leafhopper Macrosteles quadripunctulatus (Hemiptera: Cicadellidae). Genome Announc 4:e01604-15. doi:10.1128/genomeA.01604-15. PubMed DOI PMC

McCutcheon JP, McDonald BR, Moran NA. 2009. Convergent evolution of metabolic roles in bacterial co-symbionts of insects. Proc Natl Acad Sci USA 106:15394–15399. doi:10.1073/pnas.0906424106. PubMed DOI PMC

Bennett GM, Mao M. 2018. Comparative genomics of a quadripartite symbiosis in a planthopper host reveals the origins and rearranged nutritional responsibilities of anciently diverged bacterial lineages. Environ Microbiol 20:4461–4472. doi:10.1111/1462-2920.14367. PubMed DOI

Akman L, Yamashita A, Watanabe H, Oshima K, Shiba T, Hattori M, Aksoy S. 2002. Genome sequence of the endocellular obligate symbiont of tsetse flies, Wigglesworthia glossinidia. Nat Genet 32:402–407. doi:10.1038/ng986. PubMed DOI

Rio RVM, Symula RE, Wang J, Lohs C, Wu Y, Snyder AK, Bjornson RD, Oshima K, Biehl BS, Perna NT, Hattori M, Aksoy S. 2012. Insight into the transmission biology and species-specific functional capabilities of tsetse (Diptera: Glossinidae) obligate symbiont Wigglesworthia. mBio 3:e00240-11. doi:10.1128/mBio.00240-11. PubMed DOI PMC

Kirkness EF, Haas BJ, Sun W, Braig HR, Perotti MA, Clark JM, Lee SH, Robertson HM, Kennedy RC, Elhaik E, Gerlach D, Kriventseva EV, Elsik CG, Graur D, Hill CA, Veenstra JA, Walenz B, Tubío JMC, Ribeiro JMC, Rozas J, Johnston JS, Reese JT, Popadic A, Tojo M, Raoult D, Reed DL, Tomoyasu Y, Kraus E, Mittapalli O, Margam VM, Li H-M, Meyer JM, Johnson RM, Romero-Severson J, VanZee JP, Alvarez-Ponce D, Vieira FG, Aguadé M, Guirao-Rico S, Anzola JM, Yoon KS, Strycharz JP, Unger MF, Christley S, Lobo NF, Seufferheld MJ, Wang N, Dasch GA, Struchiner CJ, Madey G, et al. . 2010. Genome sequences of the human body louse and its primary endosymbiont provide insights into the permanent parasitic lifestyle. Proc Natl Acad Sci USA 107:12168–12173. doi:10.1073/pnas.1003379107. PubMed DOI PMC

Price DR, Wilson AC. 2014. A substrate ambiguous enzyme facilitates genome reduction in an intracellular symbiont. BMC Biol 12:110. doi:10.1186/s12915-014-0110-4. PubMed DOI PMC

González-Domenech CM, Belda E, Patiño-Navarrete R, Moya A, Peretó J, Latorre A. 2012. Metabolic stasis in an ancient symbiosis: genome-scale metabolic networks from two Blattabacterium cuenoti strains, primary endosymbionts of cockroaches. BMC Microbiol 12:S5. doi:10.1186/1471-2180-12-S1-S5. PubMed DOI PMC

Ponce-de-León M, Montero F, Peretó J. 2013. Solving gap metabolites and blocked reactions in genome-scale models: application to the metabolic network of Blattabacterium cuenoti. BMC Syst Biol 7:114. doi:10.1186/1752-0509-7-114. PubMed DOI PMC

Patino-Navarrete R, Piulachs M-D, Belles X, Moya A, Latorre A, Peretó J. 2014. The cockroach Blattella germanica obtains nitrogen from uric acid through a metabolic pathway shared with its bacterial endosymbiont. Biol Lett 10:20140407. doi:10.1098/rsbl.2014.0407. PubMed DOI PMC

Zhang H, Yoshizawa S, Sun Y, Huang Y, Chu X, González JM, Pinhassi J, Luo H. 2019. Repeated evolutionary transitions of flavobacteria from marine to non-marine habitats. Environ Microbiol 21:648–666. doi:10.1111/1462-2920.14509. PubMed DOI

Wakayama EJ, Dillwith JW, Howard RW, Blomquist GJ. 1984. Vitamin B12 levels in selected insects. Insect Biochem 14:175–179. doi:10.1016/0020-1790(84)90027-1. DOI

Schmidt A, Call L-M, Macheiner L, Mayer HK. 2019. Determination of vitamin B12 in four edible insect species by immunoaffinity and ultra-high performance liquid chromatography. Food Chem 281:124–129. doi:10.1016/j.foodchem.2018.12.039. PubMed DOI

Brzuszkiewicz E, Waschkowitz T, Wiezer A, Daniel R. 2012. Complete genome sequence of the B12-producing Shimwellia blattae Strain DSM 4481, isolated from a cockroach. J Bacteriol 194:4436–4436. doi:10.1128/JB.00829-12. PubMed DOI PMC

Zhang Y, Rodionov DA, Gelfand MS, Gladyshev VN. 2009. Comparative genomic analyses of nickel, cobalt and vitamin B12 utilization. BMC Genomics 10:78. doi:10.1186/1471-2164-10-78. PubMed DOI PMC

Buchner P. 1965. Endosymbiosis of animals with plant microorganims. John Wiley Sons, Hoboken, New Jersey.

Koga R, Bennett GM, Cryan JR, Moran NA. 2013. Evolutionary replacement of obligate symbionts in an ancient and diverse insect lineage. Environ Microbiol 15:2073–2081. doi:10.1111/1462-2920.12121. PubMed DOI

Mao M, Yang X, Bennett GM. 2018. Evolution of host support for two ancient bacterial symbionts with differentially degraded genomes in a leafhopper host. Proc Natl Acad Sci USA 115:E11691–E11700. PubMed PMC

Potrikus CJ, Breznak JA. 1981. Gut bacteria recycle uric acid nitrogen in termites: a strategy for nutrient conservation. Proc Natl Acad Sci USA 78:4601–4605. doi:10.1073/pnas.78.7.4601. PubMed DOI PMC

Li S, Zhu S, Jia Q, Yuan D, Ren C, Li K, Liu S, Cui Y, Zhao H, Cao Y, Fang G, Li D, Zhao X, Zhang J, Yue Q, Fan Y, Yu X, Feng Q, Zhan S. 2018. The genomic and functional landscapes of developmental plasticity in the American cockroach. Nat Commun 9:1008. doi:10.1038/s41467-018-03281-1. PubMed DOI PMC

Terrapon N, Li C, Robertson HM, Ji L, Meng X, Booth W, Chen Z, Childers CP, Glastad KM, Gokhale K, Gowin J, Gronenberg W, Hermansen RA, Hu H, Hunt BG, Huylmans AK, Khalil SM, Mitchell RD, Munoz-Torres MC, Mustard JA, Pan H, Reese JT, Scharf ME, Sun F, Vogel H, Xiao J, Yang W, Yang Z, Yang Z, Zhou J, Zhu J, Brent CS, Elsik CG, Goodisman MA, Liberles DA, Roe RM, Vargo EL, Vilcinskas A, Wang J, Bornberg-Bauer E, Korb J, Zhang G, Liebig J. 2014. Molecular traces of alternative social organization in a termite genome. Nat Commun 5:3636. doi:10.1038/ncomms4636. PubMed DOI

Hayashi Y, Maekawa K, Nalepa CA, Miura T, Shigenobu S. 2017. Transcriptome sequencing and estimation of DNA methylation level in the subsocial wood-feeding cockroach Cryptocercus punctulatus (Blattodea: Cryptocercidae). Appl Entomol Zool 52:643–651. doi:10.1007/s13355-017-0519-7. DOI

Harrison MC, Jongepier E, Robertson HM, Arning N, Bitard-Feildel T, Chao H, Childers CP, Dinh H, Doddapaneni H, Dugan S, Gowin J, Greiner C, Han Y, Hu H, Hughes DST, Huylmans AK, Kemena C, Kremer LPM, Lee SL, Lopez-Ezquerra A, Mallet L, Monroy-Kuhn JM, Moser A, Murali SC, Muzny DM, Otani S, Piulachs MD, Poelchau M, Qu J, Schaub F, Wada-Katsumata A, Worley KC, Xie Q, Ylla G, Poulsen M, Gibbs RA, Schal C, Richards S, Belles X, Korb J, Bornberg-Bauer E. 2018. Hemimetabolous genomes reveal molecular basis of termite eusociality. Nat Ecol Evol 2:557–566. doi:10.1038/s41559-017-0459-1. PubMed DOI PMC

Seppey M, Manni M, Zdobnov EM. 2019. BUSCO: assessing genome assembly and annotation completeness, p 227–245. In Kollmar M (ed), Gene Prediction: Methods and Protocols. Springer, New York, NY. PubMed

Blankenburg S, Balfanz S, Hayashi Y, Shigenobu S, Miura T, Baumann O, Baumann A, Blenau W. 2015. Cockroach GABAB receptor subtypes: molecular characterization, pharmacological properties and tissue distribution. Neuropharmacology 88:134–144. doi:10.1016/j.neuropharm.2014.08.022. PubMed DOI

Lechner M, Findeiss S, Steiner L, Marz M, Stadler PF, Prohaska SJ. 2011. Proteinortho: detection of (co-)orthologs in large-scale analysis. BMC Bioinformatics 12:124. doi:10.1186/1471-2105-12-124. PubMed DOI PMC

Wu M, Scott AJ. 2012. Phylogenomic analysis of bacterial and archaeal sequences with AMPHORA2. Bioinformatics 28:1033–1034. doi:10.1093/bioinformatics/bts079. PubMed DOI

Katoh K, Kuma K, Toh H, Miyata T. 2005. MAFFT version 5: improvement in accuracy of multiple sequence alignment. Nucleic Acids Res 33:511–518. doi:10.1093/nar/gki198. PubMed DOI PMC

Castresana J. 2000. Selection of conserved blocks from multiple alignments for their use in phylogenetic analysis. Mol Biol Evol 17:540–552. doi:10.1093/oxfordjournals.molbev.a026334. PubMed DOI

Kück P, Longo GC. 2014. FASconCAT-G: extensive functions for multiple sequence alignment preparations concerning phylogenetic studies. Front Zool 11:81. doi:10.1186/s12983-014-0081-x. PubMed DOI PMC

Hrdy I, Hirt RP, Dolezal P, Bardonová L, Foster PG, Tachezy J, Martin Embley T. 2004. Trichomonas hydrogenosomes contain the NADH dehydrogenase module of mitochondrial complex I. Nature 432:618–622. doi:10.1038/nature03149. PubMed DOI

Stamatakis A. 2014. RAxML version 8: a tool for phylogenetic analysis and post-analysis of large phylogenies. Bioinformatics 30:1312–1313. doi:10.1093/bioinformatics/btu033. PubMed DOI PMC

Kriventseva EV, Kuznetsov D, Tegenfeldt F, Manni M, Dias R, Simão FA, Zdobnov EM. 2019. OrthoDB v10: sampling the diversity of animal, plant, fungal, protist, bacterial and viral genomes for evolutionary and functional annotations of orthologs. Nucleic Acids Res 47:D807–D811. doi:10.1093/nar/gky1053. PubMed DOI PMC

Rognes T, Flouri T, Nichols B, Quince C, Mahé F. 2016. VSEARCH: a versatile open source tool for metagenomics. PeerJ 4:e2584. doi:10.7717/peerj.2584. PubMed DOI PMC

Jones CE, Brown AL, Baumann U. 2007. Estimating the annotation error rate of curated GO database sequence annotations. BMC Bioinformatics 8:170. doi:10.1186/1471-2105-8-170. PubMed DOI PMC

Jones P, Binns D, Chang HY, Fraser M, Li W, McAnulla C, McWilliam H, Maslen J, Mitchell A, Nuka G, Pesseat S, Quinn AF, Sangrador-Vegas A, Scheremetjew M, Yong SY, Lopez R, Hunter S. 2014. InterProScan 5: Genome-scale protein function classification. Bioinformatics 30:1236–1240. doi:10.1093/bioinformatics/btu031. PubMed DOI PMC

Marchler-Bauer A, Bo Y, Han L, He J, Lanczycki CJ, Lu S, Chitsaz F, Derbyshire MK, Geer RC, Gonzales NR, Gwadz M, Hurwitz DI, Lu F, Marchler GH, Song JS, Thanki N, Wang Z, Yamashita RA, Zhang D, Zheng C, Geer LY, Bryant SH. 2017. CDD/SPARCLE: functional classification of proteins via subfamily domain architectures. Nucleic Acids Res 45:D200–D203. doi:10.1093/nar/gkw1129. PubMed DOI PMC

Camon EB, Barrell DG, Dimmer EC, Lee V, Magrane M, Maslen J, Binns D, Apweiler R. 2005. An evaluation of GO annotation retrieval for BioCreAtIvE and GOA. BMC Bioinformatics 6:S1–S17. doi:10.1186/1471-2105-6-S1-S17. PubMed DOI PMC

De Ferrari L, Aitken S, van Hemert J, Goryanin I. 2012. EnzML: multi-label prediction of enzyme classes using InterPro signatures. BMC Bioinformatics 13:61. doi:10.1186/1471-2105-13-61. PubMed DOI PMC

Tatusov RL, Galperin MY, Natale DA, Koonin EV. 2000. The COG database: a tool for genome-scale analysis of protein functions and evolution. Nucleic Acids Res 28:33–36. doi:10.1093/nar/28.1.33. PubMed DOI PMC

Caspi R, Billington R, Keseler IM, Kothari A, Krummenacker M, Midford PE, Ong WK, Paley S, Subhraveti P, Karp PD. 2020. The MetaCyc database of metabolic pathways and enzymes - a 2019 update. Nucleic Acids Res 48:D445–D453. doi:10.1093/nar/gkz862. PubMed DOI PMC

Jeske L, Placzek S, Schomburg I, Chang A, Schomburg D. 2019. BRENDA in 2019: a European ELIXIR core data resource. Nucleic Acids Res 47:D542–D549. doi:10.1093/nar/gky1048. PubMed DOI PMC

Pellegrini M, Marcotte EM, Thompson MJ, Eisenberg D, Yeates TO. 1999. Assigning protein functions by comparative genome analysis: Protein phylogenetic profiles. Proc Natl Acad Sci USA 96:4285–4288. doi:10.1073/pnas.96.8.4285. PubMed DOI PMC

Osterman A, Overbeek R. 2003. Missing genes in metabolic pathways: a comparative genomics approach. Curr Opin Chem Biol 7:238–251. doi:10.1016/s1367-5931(03)00027-9. PubMed DOI

Chen L, Vitkup D. 2006. Predicting genes for orphan metabolic activities using phylogenetic profiles. Genome Biol 7:R17. doi:10.1186/gb-2006-7-2-r17. PubMed DOI PMC

Hernández-Montes G, Díaz-Mejía JJ, Pérez-Rueda E, Segovia L. 2008. The hidden universal distribution of amino acid biosynthetic networks: a genomic perspective on their origins and evolution. Genome Biol 9:R95. doi:10.1186/gb-2008-9-6-r95. PubMed DOI PMC

Reimer LC, Vetcininova A, Carbasse JS, Söhngen C, Gleim D, Ebeling C, Overmann J. 2019. BacDive in 2019: bacterial phenotypic data for high-throughput biodiversity analysis. Nucleic Acids Res 47:D631–D636. doi:10.1093/nar/gky879. PubMed DOI PMC

Highly Resolved Genomes of Two Closely Related Lineages of the Rodent Louse Polyplax serrata with Different Host Specificities