Abstract
Transmission pathways have fundamental influence on microbial symbiont persistence and evolution. For example, the core gut microbiome of honey bees is transmitted socially and via hive surfaces, but some non-core bacteria associated with honey bees are also found on flowers, and these bacteria may therefore be transmitted indirectly between bees via flowers. Here, we test whether multiple flower and wild megachilid bee species share microbes, which would suggest that flowers may act as hubs of microbial transmission. We sampled the microbiomes of flowers (either bagged to exclude bees or open to allow bee visitation), adults, and larvae of seven megachilid bee species and their pollen provisions. We found a Lactobacillus operational taxonomic unit (OTU) in all samples but in the highest relative and absolute abundances in adult and larval bee guts and pollen provisions. The presence of the same bacterial types in open and bagged flowers, pollen provisions, and bees supports the hypothesis that flowers act as hubs of transmission of these bacteria between bees. The presence of bee-associated bacteria in flowers that have not been visited by bees suggests that these bacteria may also be transmitted to flowers via plant surfaces, the air, or minute insect vectors such as thrips. Phylogenetic analyses of nearly full-length 16S rRNA gene sequences indicated that the Lactobacillus OTU dominating in flower- and megachilid-associated microbiomes is monophyletic, and we propose the name Lactobacillus micheneri sp. nov. for this bacterium.
This is a preview of subscription content, access via your institution.





References
Goodrich JK, Davenport ER, Waters JL et al (2016) Cross-species comparisons of host genetic associations with the microbiome. Science 352:532–535. doi:10.1126/science.aad9379
Moeller AH, Caro-Quintero A, Mjungu D et al (2016) Cospeciation of gut microbiota with hominids. Science 353:380–382. doi:10.1126/science.aaf3951
Engel P, Moran NA (2013) The gut microbiota of insects—diversity in structure and function. FEMS Microbiol Rev 37:699–735. doi:10.1111/1574-6976.12025
Chaston J, Goodrich-Blair H (2010) Common trends in mutualism revealed by model associations between invertebrates and bacteria. FEMS Microbiol Rev 34:41–58. doi:10.1111/j.1574-6976.2009.00193.x
Sachs J, Mueller U, Wilcox T, Bull J (2004) The evolution of cooperation. Q Rev Biol 79:135–160
Werren JH, Baldo L, Clark ME (2008) Wolbachia: master manipulators of invertebrate biology. Nat Rev Microbiol 6:741–751. doi:10.1038/nrmicro1969
Smith CC, Mueller UG (2015) Sexual transmission of beneficial microbes. Trends Ecol Evol 30:438–440. doi:10.1016/j.tree.2015.05.006
Kikuchi Y, Hosokawa T, Fukatsu T (2007) Insect-microbe mutualism without vertical transmission: a stinkbug acquires a beneficial gut symbiont from the environment every generation. Appl Environ Microbiol 73:4308–4316. doi:10.1128/AEM.00067-07
Martinson VG, Moy J, Moran NA (2012) Establishment of characteristic gut bacteria during development of the honeybee worker. Appl Environ Microbiol 78:2830–2840. doi:10.1128/AEM.07810-11
Koch H, Schmid-Hempel P (2011) Socially transmitted gut microbiota protect bumble bees against an intestinal parasite. Proc Natl Acad Sci 108:19288–19292. doi:10.1073/pnas.1110474108
Powell JE, Martinson VG, Urban-Mead K, Moran NA (2014) Routes of acquisition of the gut microbiota of the honey bee Apis mellifera. Appl Environ Microbiol 80:7378–7387. doi:10.1128/AEM.01861-14
Martinson VG, Danforth BN, Minckley RL et al (2011) A simple and distinctive microbiota associated with honey bees and bumble bees. Mol Ecol 20:619–628. doi:10.1111/j.1365-294X.2010.04959.x
McFrederick QS, Wcislo WT, Taylor DR et al (2012) Environment or kin: whence do bees obtain acidophilic bacteria? Mol Ecol 21:1754–1768. doi:10.1111/j.1365-294X.2012.05496.x
McFrederick QS, Mueller UG, James RR (2014) Interactions between fungi and bacteria influence microbial community structure in the Megachile rotundata larval gut. Proc R Soc B B Sci 281:20132653
McFrederick QS, Cannone JJ, Gutell RR et al (2013) Specificity between lactobacilli and hymenopteran hosts is the exception rather than the rule. Appl Environ Microbiol 79:1803–1812. doi:10.1128/AEM.03681-12
McFrederick QS, Rehan SM (2016) Characterization of pollen and bacterial community composition in brood provisions of a small carpenter bee. Mol Ecol 25:2302–2311. doi:10.1111/mec.13608
Anderson KE, Sheehan TH, Mott BM et al (2013) Microbial ecology of the hive and pollination landscape: bacterial associates from floral nectar, the alimentary tract and stored food of honey bees (Apis mellifera). PLoS One 8:e83125. doi:10.1371/journal.pone.0083125.s012
Vojvodic S, Rehan SM, Anderson KE (2013) Microbial gut diversity of Africanized and European honey bee larval instars. PLoS One 8:e72106. doi:10.1371/journal.pone.0072106
McFrederick QS, Wcislo WT, Hout MC, Mueller UG (2014) Host species and developmental stage, but not host social structure, affects bacterial community structure in socially polymorphic bees. FEMS Microbiol Ecol 88:398–406. doi:10.1111/1574-6941.12302
Cane J (2006) The Logan Beemail shelter: a practical, portable unit for managing cavity nesting agricultural pollinators. Am Bee J 146:611–613
Sen R, Ishak HD, Estrada DA et al (2009) Generalized antifungal activity and 454-screening of Pseudonocardia and Amycolatopsis bacteria in nests of fungus-growing ants. Proc Natl Acad Sci 106:17805–17810
Engel P, James RR, Koga R et al (2013) Standard methods for research on Apis mellifera gut symbionts. J Apic Res 52:1–24. doi:10.3896/IBRA.1.52.4.07
Moran NA, Hansen AK, Powell JE, Sabree ZL (2012) Distinctive gut microbiota of honey bees assessed using deep sampling from individual worker bees. PLoS One 7:e36393. doi:10.1371/journal.pone.0036393.t005
Mattila HR, Rios D, Walker-Sperling VE et al (2012) Characterization of the active microbiotas associated with honey bees reveals healthier and broader communities when colonies are genetically diverse. PLoS One 7:e32962. doi:10.1371/journal.pone.0032962.t002
Caporaso JG, Kuczynski J, Stombaugh J et al (2010) QIIME allows analysis of high-throughput community sequencing data. Nat Methods 7:335–336
Edgar RC (2010) Search and clustering orders of magnitude faster than BLAST. Bioinformatics 26:2460–2461. doi:10.1093/bioinformatics/btq461
Kopylova E, Navas-Molina JA, Mercier C et al (2016) Open-source sequence clustering methods improve the state of the art. mSystems 1:e00003–15. doi: 10.1128/mSystems.00003-15
Wang Q, Garrity GM, Tiedje JM, Cole JR (2007) Naive Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy. Appl Environ Microbiol 73:5261–5267. doi:10.1128/AEM.00062-07
McDonald D, Price MN, Goodrich J et al (2012) An improved Greengenes taxonomy with explicit ranks for ecological and evolutionary analyses of bacteria and archaea. ISME J 6:610–618. doi:10.1038/ismej.2011.139
Caporaso JG, Bittinger K, Bushman FD et al (2010) PyNAST: a flexible tool for aligning sequences to a template alignment. Bioinformatics 26:266–267. doi:10.1093/bioinformatics/btp636
Maddison W, Maddison DR Mesquite: a modular system for evolutionary analysis
Price MN, Dehal PS, Arkin AP (2009) FastTree: computing large minimum evolution trees with profiles instead of a distance matrix. Mol Biol Evol 26:1641–1650. doi:10.1093/molbev/msp077
R core development team R: a language and environment for statistical computing
Warnes GR, Bolker B, Bonebakker L et al (2015) gplots: various R programming tool for plotting data
Good IJ (1953) The population frequencies of species and the estimation of population parameters. Biometrika 40:237–264. doi:10.1093/biomet/40.3-4.237
Hamady M, Lozupone C (2009) Fast UniFrac: facilitating high-throughput phylogenetic analyses of microbial communities including analysis of pyrosequencing and PhyloChip data. ISME J 4:17–27
Chen J, Bittinger K, Charlson ES et al (2012) Associating microbiome composition with environmental covariates using generalized UniFrac distances. Bioinformatics 28:2106–2113. doi:10.1093/bioinformatics/bts342
Oksanen J, Blanchet FG, Kindt R et al vegan: community ecology package
Ye J, Coulouris G, Zaretskaya I et al (2012) Primer-BLAST: a tool to design target-specific primers for polymerase chain reaction. BMC Bioinf 13:134. doi:10.1016/0022-2836(70)90057-4
Turner S, Pryer KM, Miao VP, Palmer JD (1999) Investigating deep phylogenetic relationships among cyanobacteria and plastids by small subunit rRNA sequence analysis. J Eukaryot Microbiol 46:327–338. doi:10.1111/j.1550-7408.1999.tb04612.x
Lane DJ (1991) 16S/23S rRNA sequencing. In: Stackebrandt E, Goodfellow M (eds) Nucleic acid techniques in bacterial systematics. John Wiley & Sons, New York, NY, pp 115–175
De Man JC, Rogosa M, Sharpe ME (1960) A medium for the cultivation of lactobacilli. J Appl Microbiol 23:130–135. doi:10.1111/j.1365-2672.1960.tb00188.x
Olofsson TC, Alsterfjord M, Nilson B et al (2014) Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov., isolated from the honey stomach of the honeybee Apis mellifera. Int J Syst Evol Microbiol 64:3109–3119. doi:10.1099/ijs.0.059600-0
Benson DA, Cavanaugh M, Clark K et al (2013) GenBank. Nucleic Acids Res 41:D36–D42. doi:10.1093/nar/gks1195
Koch H, Abrol DP, Li J, Schmid-Hempel P (2013) Diversity and evolutionary patterns of bacterial gut associates of corbiculate bees. Mol Ecol 22:2028–2044. doi:10.1111/mec.12209
Huang Y, Niu B, Gao Y, Fu L (2010) CD-HIT Suite: a web server for clustering and comparing biological sequences. Bioinformatics 26:680–682
Nováková E, Hypša V, Moran NA (2009) Arsenophonus, an emerging clade of intracellular symbionts with a broad host distribution. BMC Microbiol 9:143. doi:10.1186/1471-2180-9-143
Stamatakis A (2006) RAxML-VI-HPC: maximum likelihood-based phylogenetic analyses with thousands of taxa and mixed models. Bioinformatics 22:2688–2690. doi:10.1093/bioinformatics/btl446
Miller MA, Pfeiffer W, Schwartz T (2010) Creating the CIPRES Science Gateway for inference of large phylogenetic trees. In: Proceedings of the Gateway Computing Enviropnments. New Orleans, LA, pp 1–8
Anderson KE, Carroll MJ, Sheehan T et al (2014) Hive-stored pollen of honey bees: many lines of evidence are consistent with pollen preservation, not nutrient conversion. Mol Ecol 23:5904–5917. doi:10.1111/mec.12966
Corby-Harris V, Maes P, Anderson KE (2014) The bacterial communities associated with honey bee (Apis mellifera) foragers. PLoS One 9:e95056
Edwards C, Haag K, Collins M et al (1998) Lactobacillus kunkeei sp. nov.: a spoilage organism associated with grape juice fermentations. J Appl Microbiol 84:698–702
Corby-Harris V, Snyder LA, Schwan MR et al (2014) Origin and effect of alpha 2.2 Acetobacteraceae in honey bee larvae and description of Parasaccharibacter apium gen. nov., sp. nov. Appl Environ Microbiol 80:7460–7472. doi:10.1128/AEM.02043-14
Graystock P, Goulson D, Hughes WOH (2015) Parasites in bloom: flowers aid dispersal and transmission of pollinator parasites within and between bee species. Proc R Soc B Biol Sci 282:20151371. doi:10.1098/rspb.2015.1371
Finlay BJ, Fenchel T (2004) Cosmopolitan metapopulations of free-living microbial eukaryotes. Protist 155:237–244
Lindemann J, Constantinidou HA, Barchet WR, Upper CD (1982) Plants as sources of airborne bacteria, including ice nucleation-active bacteria. Appl Environ Microbiol 44:1059–1063
University of California IPM (2013) Floriculture & ornamental nurseries. In: University of California Agriculture and Natural Resources Publication 3392. http://www.ipm.ucdavis.edu/PDF/PMG/pmgfloriculture.pdf. Accessed 19 May 2015
Durrer S, Schmid-Hempel P (1994) Shared use of flowers leads to horizontal pathogen transmission. Proc R Soc B Biol Sci 258:299–302
Ushio M, Yamasaki E, Takasu H et al (2015) Microbial communities on flower surfaces act as signatures of pollinator visitation. Sci Rep 5:8695. doi:10.1038/srep08695
Aizenberg-Gershtein Y, Izhaki I, Halpern M (2013) Do honeybees shape the bacterial community composition in floral nectar? PLoS One 8:e67556. doi:10.1371/journal.pone.0067556
Klostermeyer EC, Mech SJ Jr, Rasmussen WB (1973) Sex and weight of Megachile rotundata (Hymenoptera: Megachilidae) progeny associated with provision weights. J Kansas Entomol Soc 46:536–548
Kwong WK, Moran NA (2015) Evolution of host specialization in gut microbes: the bee gut as a model. Gut Microbes 6:214–220. doi:10.1080/19490976.2015.1047129
Kwong WK, Engel P, Koch H, Moran NA (2014) Genomics and host specialization of honey bee and bumble bee gut symbionts. PNAS 111:11509–11514. doi:10.1073/pnas.1405838111
Kwong WK, Moran NA (2013) Cultivation and characterization of the gut symbionts of honey bees and bumble bees: Snodgrassella alvi gen. nov., sp. nov., a member of the Neisseriaceae family of the Betaproteobacteria; and Gilliamella apicola gen. nov., sp. nov., a member of Orbaceae fam. nov., Orbales ord. nov., a sister taxon to the Enterobacteriales order of the Gammaproteobacteria. Int J Syst Evol Microbiol 63:2008–2018. doi:10.1099/ijs.0.044875-0
Gerth M, Saeed A, White JA, Bleidorn C (2015) Extensive screen for bacterial endosymbionts reveals taxon-specific distribution patterns among bees (Hymenoptera, Anthophila). FEMS Microbiol Ecol 91:fiv047–fiv047. doi:10.1093/femsec/fiv047
Acknowledgments
The work was supported by the National Science Foundation under award no. PRFB-1003133 awarded to QSM and award DEB-0919519 to UGM and by UC Riverside initial complement funds to QSM. The Texas Ecolab provided access to private land and funding for fieldwork and sequencing. We especially thank Mike and MaryAnn Johansen for access to their Ecolab property. We thank Kirk E Anderson, Peter Graystock, and Jason Rothman for the helpful comments on an earlier draft of the manuscript. We thank Pearl Le and Duane Kim for assisting with the bioinformatic analyses.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
McFrederick, Q.S., Thomas, J.M., Neff, J.L. et al. Flowers and Wild Megachilid Bees Share Microbes. Microb Ecol 73, 188–200 (2017). https://doi.org/10.1007/s00248-016-0838-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00248-016-0838-1