Gammaproteobacteria

Gammaproteobacteria
Vibrio cholerae
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Pseudomonadota
Class: Gammaproteobacteria
Garrity et al. 2005
Orders
Synonyms
  • "Chromatiia" Cavalier-Smith 2020

Gammaproteobacteria is a class of bacteria in the phylum Pseudomonadota (synonym Proteobacteria). It contains about 250 genera, which makes it the most genus-rich taxon of the Prokaryotes.[1] Several medically, ecologically, and scientifically important groups of bacteria belong to this class. All members of this class are Gram-negative. It is the most phylogenetically and physiologically diverse class of the Pseudomonadota.[2]

Members of Gammaproteobacteria live in several terrestrial and marine environments, in which they play various important roles, including in extreme environments such as hydrothermal vents. They can have different shapes, rods, curved rods, cocci, spirilla, and filaments,[3] and include free living bacteria, biofilm formers, commensals and symbionts;[4] some also have the distinctive trait of being bioluminescent.[5] Diverse metabolisms are found in Gammaproteobacteria; there are both aerobic and anaerobic (obligate or facultative) species, chemolithoautotrophics, chemoorganotrophics, photoautotrophs and heterotrophs.[6]

Etymology

The element "gamma" (third letter of the Greek alphabet) indicates that this is Class III in Bergey's Manual of Systematic Bacteriology (Vol. II, page 1). Proteus refers to the Greek sea god who could change his shape. Bacteria (Greek βακτήριον; "rod" "little stick"), in terms of etymological history, refers to Bacillus (rod-shaped bacteria), but in this case is "useful in the interim while the phylogenetic data are being integrated into formal bacterial taxonomy."[7]

Phylogeny

Currently, many different classifications are based on different approaches, such as

It is (as of 2010) still very difficult to resolve the phylogeny of this bacterial class.[4]

The following molecular phylogeny of Gammaproteobacteria is based on a set of 356 protein families.

Phylogeny of Gammaproteobacteria

Betaproteobacteria

Gammaproteobacteria
Phylogeny of Gammaproteobacteria after[4] Not all orders are monophyletic, consequently families or genera are shown for the Pseudomonadales, Oceanospirillales, and Alteromonadales. In the case of singleton orders, the genus is shown. (In bacterial taxonomy, orders have the suffix -ales, while families have -aceae.)

A number of genera in Gammaproteobacteria have not yet been assigned to an order or family. These include Alkalimonas, Gallaecimonas, Ignatzschineria, Litorivivens, Marinicella, Plasticicumulans, Pseudohongiella, Sedimenticola, Thiohalobacter, Thiohalorhabdus, Thiolapillus, and Wohlfahrtiimonas.[9]

Significance and applications

Gammaproteobacteria, especially the orders Alteromonadales and Vibrionales, are fundamental in marine and coastal ecosystems because they are the major groups involved in nutrient cycling.[10] Despite their fame as pathogens, they find application in a huge number of fields, such as bioremediation and biosynthesis.

Gammaproteobacteria can be used as a microbial fuel cell (MFC)[11] element that applies their ability to dissimilate various metals.[12] The produced energy could be collected as one of the most environmentally friendly and sustainable energy production systems.[13] They are also used as biological methane filters.[14]

Phototrophic purple sulfur bacteria are used in wastewater treatment processes.[15] The ability of some Gammaproteobacteria (e.g. the genus Alcanivorax[16]) to bioremediate oil is increasingly important for degrading crude oil after oil spills.[17] Some species from the family Chromatiaceae are notable because they may be involved in the production of vitamin B12.[18] Some Gammaproteobacteria are used to synthesize poly-b-hydroxyalkanoate (PHA),[19] which is a polymer that is used in the production of biodegradable plastics. Many Gammaproteobacteria species are able to generate secondary metabolites with antibacterial properties.[20]

Ecology

Gammaproteobacteria are widely distributed and abundant in various ecosystems such as soil, freshwater lakes and rivers, oceans and salt lakes. For example, they constitute about 6–20% (average of 14%) of bacterioplankton in different oceans,[21] and they are distributed worldwide in both deep-sea and coastal sediments.[22] In seawater, bacterial community composition could be shaped by environmental parameters such as phosphorus availability, total organic carbon, salinity, and pH.[23] In soil, higher pH is correlated with higher relative abundance of Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria.[24] The relative abundance of Betaproteobacteria and Gammaproteobacteria is also positively correlated to the dissolved organic carbon (DOC) concentration, which is a key environmental parameter shaping bacterial community composition.[25] Gammaproteobacteria are also key players in the dark carbon fixation in coastal sediments, which are the largest carbon sink on Earth, and the majority of these bacteria have not been cultured yet.[26] The deep-sea hydrothermal system is one of the most extreme environments on Earth. Almost all vent-endemic animals are strongly associated with the primary production of the endo- and/or episymbiotic chemoautotrophic microorganisms.[27] Analyses of both the symbiotic and free-living microbial communities in the various deep-sea hydrothermal environments have revealed a predominance in biomass of members of the Gammaproteobacteria.[28]

Gammaproteobacteria have a wide diversity, metabolic versatility, and functional redundancy in the hydrothermal sediments, and they are responsible for the important organic carbon turnover and nitrogen and sulfur cycling processes.[29] Anoxic hydrothermal fluids contain several reduced compounds such as H2, CH4, and reduced metal ions in addition to H2S. Chemoautotrophs that oxidize hydrogen sulfide and reduce oxygen potentially sustain the primary production in these unique ecosystems.[30] In the last decades, it has been found that orders belonging to Gammaproteobacteria, like Pseudomonas, Moraxella, are able to degrade different types of plastics, and these microbes might have a key role in plastic biodegradation.[31]

Metabolism

Gammaproteobacteria are metabolically diverse, employing a variety of electron donors for respiration and biosynthesis.

Some groups are nitrite-oxidizers[32] and ammonia oxidizers like the members of Nitrosococcus (with the exception of Nitrosococcus mobilis) and they are also obligate halophilic bacteria.[33]

Others are chemoautotrophic sulfur-oxidizers, like Thiotrichales, which are found in communities such as filamentous microbial biofilms in the Tor Caldara shallow-water gas vent in the Tyrrhenian Sea.[34] Moreover, thanks to 16S rRNA gene analysis, different sulfide oxidizers in the Gammaporteobacteria class have been detected, and the most important among them are Beggiatoa, Thioploca and Thiomargarita; besides, large amounts of hydrogen sulfide are produced by sulfate-reducing bacteria in organic-rich coastal sediments.[35]

Marine Gammaproteobacteria include aerobic anoxygenic phototrophic bacteria (AAP) that use bacteriochlorophyll to support the electron transport chain. They are believed to be a widespread and essential community in the oceans.[36]

Methanotrophs, such as the order Methylococcales, metabolize methane as sole energy source and are very important in the global carbon cycle. They are found in any site with methane sources, like gas reserves, soils, and wastewater.[37]

Purple sulfur bacteria are anoxygenic phototrophs that oxidize sulfur,[38] but potentially also other substrates like iron.[39] They are represented by members of two families, Chromatiaceae (e.g. Allochromatium, Chromatium, Thiodicyton) and Ectothiorhodospiraceae (e.g. Ectothiorhodospira).[38] A few species within the genus Thermomonas (order Lysobacter) carry out the same metabolism.[40]

Numerous genera are obligate or generalist hydrocarbonclasts. The obligate hydrocarbonoclastic bacteria (OHCB) use hydrocarbons almost exclusively as a carbon source; until now[when?] they have been found only in the marine environment. Examples include Alcanivorax, Oleiphilus, Oleispira, Thalassolitus, Cycloclasticus and Neptunomonas, and some species of Polycyclovorans, Algiphilus (order Xanthomonadales), and Porticoccus hydrocarbonoclasticus (order Cellvibrionales) that were isolated from phytoplankton. In contrast, aerobic “generalist” hydrocarbon degraders can use either hydrocarbons or nonhydrocarbon substrates as sources of carbon and energy; examples are found in the genera Acinetobacter, Colwellia, Glaciecola, Halomonas, Marinobacter, Marinomonas, Methylomonas, Pseudoalteromonas, Pseudomonas, Rhodanobacter, Shewanella, Stenotrophomonas, and Vibrio.[41]

The most widespread pathway for carbon fixation among Gammaproteobacteria is the Calvin–Benson–Bassham (CBB) cycle, although a minority may use the rTCA cycle.[42] Thioflavicoccus mobilis (a free living species) and "Candidatus Endoriftia persephone" (symbiont of the giant tubeworm Riftia pachyptila) may use the rTCA cycle in addition to the CBB cycle, and may express these two different pathways simultaneously.[43]

Symbiosis

Symbiosis is a close and a long-term biological interaction between two different biological organisms. A large number of Gammaproteobacteria are able to join in a close endosymbiosis with various species. Evidence for this can be found in a wide variety of ecological niches: on the ground,[44][45] within plants,[46] or deep on the ocean floor.[47] On the land, it has been reported that Gammaproteobacteria species have been isolated from Robinia pseudoacacia[48] and other plants,[49][50] while in the deep sea a sulfur-oxidizing gammaproteobacteria was found in a hydrothermal vent chimney;[51] by entering into symbiotic relationships in deep sea areas, sulfur-oxidizing chemolithotrophic microbes receive additional organic hydrocarbons in hydrothermal ecosystems. Some Gammaproteobacteria are symbiotic with geothermic ocean vent-downwelling animals,[52] and in addition, Gammaproteobacteria can have complex relationships with other species that live around thermal springs,[53] for example, with the shrimp Rimicaris exoculata living from hydrothermal vents on the Mid-Atlantic Ridge.

Regarding the endosymbionts, most of them lack many of their family characteristics due to significant genome reduction.[54][55]

Pathogens

Gammaproteobacteria include several medically and scientifically important groups of bacteria, such as the families Enterobacteriaceae, Vibrionaceae, and Pseudomonadaceae. A number of human pathogens belong to this class, including Yersinia pestis, Vibrio cholerae, Pseudomonas aeruginosa, Escherichia coli, and some species of Salmonella. The class also contains plant pathogens such as Xanthomonas axonopodis pv. citri (citrus canker), Pseudomonas syringae pv. actinidiae (kiwifruit Psa outbreak), and Xylella fastidiosa. In the marine environment, several species from this class can infect different marine organisms, such as species in the genus Vibrio which affect fish, shrimp, corals or oysters,[56] and species of Salmonella which affect grey seals (Halichoerus grypus).[57][58]

See also

References

  1. ^ Garrity GM, Bell JA, Lilburn TG. (2005). Class III. Gammaproteobacteria class. nov. In: Brenner DJ, Krieg NR, Staley JT, Garrity GM (eds) Bergey's Manual of Systematic Bacteriology 2nd edn, vol. 2 Springer: New York, p 1
  2. ^ Gutierrez T (2019). Institute of Mechanical, Process and Energy Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
  3. ^ Schulz HN, Brinkhoff T, Ferdelman TG, Mariné MH, Teske A, Jorgensen BB (April 1999). "Dense populations of a giant sulfur bacterium in Namibian shelf sediments". Science. 284 (5413): 493–5. Bibcode:1999Sci...284..493S. doi:10.1126/science.284.5413.493. PMID 10205058.
  4. ^ a b c d Williams KP, Gillespie JJ, Sobral BW, Nordberg EK, Snyder EE, Shallom JM, Dickerman AW (May 2010). "Phylogeny of gammaproteobacteria". Journal of Bacteriology. 192 (9): 2305–14. doi:10.1128/JB.01480-09. PMC 2863478. PMID 20207755.
  5. ^ Munn CB (2019-11-26). Marine Microbiology: Ecology & Applications. CRC Press. ISBN 978-0-429-59236-2.
  6. ^ "Proteobacteria | Microbiology". Nursing Hero (study guide). 2016.
  7. ^ Stackebrandt, E.; Murray, R. G. E.; Truper, H. G. (1988). "Proteobacteria classis nov., a Name for the Phylogenetic Taxon That Includes the "Purple Bacteria and Their Relatives"". International Journal of Systematic Bacteriology. 38 (3): 321–325. doi:10.1099/00207713-38-3-321. ISSN 0020-7713.
  8. ^ "Silva". www.arb-silva.de. Retrieved 2020-11-22.
  9. ^ "Classification of domains and phyla - Hierarchical classification of prokaryotes (bacteria) - Gammaproteobacteria". List of Prokaryotic Names with Standing in Nomenclature. Retrieved 13 January 2017.
  10. ^ Evans FF, Egan S, Kjelleberg S (May 2008). "Ecology of type II secretion in marine gammaproteobacteria". Environmental Microbiology. 10 (5): 1101–7. Bibcode:2008EnvMi..10.1101E. doi:10.1111/j.1462-2920.2007.01545.x. PMID 18218035.
  11. ^ Qian F, Morse DE (February 2011). "Miniaturizing microbial fuel cells". Trends in Biotechnology. 29 (2): 62–9. doi:10.1016/j.tibtech.2010.10.003. PMID 21075467.
  12. ^ Gorby YA, Yanina S, McLean JS, Rosso KM, Moyles D, Dohnalkova A, et al. (July 2006). "Electrically conductive bacterial nanowires produced by Shewanella oneidensis strain MR-1 and other microorganisms". Proceedings of the National Academy of Sciences of the United States of America. 103 (30): 11358–63. Bibcode:2006PNAS..10311358G. doi:10.1073/pnas.0604517103. PMC 1544091. PMID 16849424.
  13. ^ Hau HH, Gralnick JA (September 2007). "Ecology and biotechnology of the genus Shewanella". Annual Review of Microbiology. 61 (1): 237–58. doi:10.1146/annurev.micro.61.080706.093257. PMID 18035608.
  14. ^ Rosenberg E, DeLong EF, Lory EF, Stackebrandt E, Erko T, Thompson F, eds. (2014). The Prokaryotes: Gammaproteobacteria (4th ed.). Berlin Heidelberg: Springer-Verlag. p. 434. ISBN 978-3-642-38921-4.
  15. ^ Kobayashi M, Michiharu T, Tchan YT (1973-08-01). "Treatment of industrial waste solutions and production of useful by-products using a photosynthetic bacterial method". Water Research. 7 (8): 1219–1224. Bibcode:1973WatRe...7.1219K. doi:10.1016/0043-1354(73)90075-4. ISSN 0043-1354.
  16. ^ Harayama S, Kishira H, Kasai Y, Shutsubo K (August 1999). "Petroleum biodegradation in marine environments". Journal of Molecular Microbiology and Biotechnology. 1 (1): 63–70. PMID 10941786.
  17. ^ Kasai Y, Kishira H, Syutsubo K, Harayama S (April 2001). "Molecular detection of marine bacterial populations on beaches contaminated by the Nakhodka tanker oil-spill accident". Environmental Microbiology. 3 (4): 246–55. Bibcode:2001EnvMi...3..246K. doi:10.1046/j.1462-2920.2001.00185.x. PMID 11359510.
  18. ^ Koppenhagen VB, Schlingmann G, Schaer W, Dresow. Moo-young M, Vezina C, Singh K (eds.). "Extracellular metabolites from phototrophic bacteria as possible intermediates in the biosynthesis of vitamin B12". Fermentation Products. Pergamon: 247–252. ISBN 978-0-08-025385-5.
  19. ^ de la Haba RR, Sánchez-Porro C, Márquez MC, Ventosa A (April 2010). "Taxonomic study of the genus Salinicola: transfer of Halomonas salaria and Chromohalobacter salarius to the genus Salinicola as Salinicola salarius comb. nov. and Salinicola halophilus nom. nov., respectively". International Journal of Systematic and Evolutionary Microbiology. 60 (Pt 4): 963–971. doi:10.1099/ijs.0.014480-0. PMID 19661506.
  20. ^ "Marine bacteria associated with marine macroorganisms: The potential antimicrobial resources - AMiner". www.aminer.org. Retrieved 2020-11-20.
  21. ^ Broszat M, Nacke H, Blasi R, Siebe C, Huebner J, Daniel R, Grohmann E. (2014). Wastewater irrigation increases the abundance of potentially harmful Gammaproteobacteria in soils in Mezquital Valley, Mexico. Appl Environ Microbiol.
  22. ^ Bienhold C, Zinger L, Boetius A, Ramette A (2016-01-27). "Diversity and Biogeography of Bathyal and Abyssal Seafloor Bacteria". Plos One. 11 (1): e0148016. Bibcode:2016PLoSO..1148016B. doi:10.1371/journal.pone.0148016. PMC 4731391. PMID 26814838.
  23. ^ Jiang H, Dong H, Ji S, Ye Y, Wu N (2007-09-26). "Microbial Diversity in the Deep Marine Sediments from the Qiongdongnan Basin in South China Sea". Geomicrobiology Journal. 24 (6): 505–517. Bibcode:2007GmbJ...24..505J. doi:10.1080/01490450701572473. S2CID 130552094.
  24. ^ Rousk J, Bååth E, Brookes PC, Lauber CL, Lozupone C, Caporaso JG, Knight R, Fierer N (October 2010). "Soil bacterial and fungal communities across a pH gradient in an arable soil". The ISME Journal. 4 (10): 1340–51. Bibcode:2010ISMEJ...4.1340R. doi:10.1038/ismej.2010.58. PMID 20445636. S2CID 205156612.
  25. ^ Li D, Sharp JO, Saikaly PE, Ali S, Alidina M, Alarawi MS, Keller S, Hoppe-Jones C, Drewes JE (October 2012). "Dissolved organic carbon influences microbial community composition and diversity in managed aquifer recharge systems". Applied and Environmental Microbiology. 78 (19): 6819–28. Bibcode:2012ApEnM..78.6819L. doi:10.1128/AEM.01223-12. PMC 3457517. PMID 22798375.
  26. ^ Hedges JI, Keil RG (April 1995). "Sedimentary organic matter preservation: an assessment and speculative synthesis". Marine Chemistry. 49 (2–3): 81–115. Bibcode:1995MarCh..49...81H. doi:10.1016/0304-4203(95)00008-F.
  27. ^ Jeanthon C (February 2000). "Molecular ecology of hydrothermal vent microbial communities". Antonie van Leeuwenhoek. 77 (2): 117–33. doi:10.1023/a:1002463825025. PMID 10768471. S2CID 24324674.
  28. ^ Stewart FJ, Newton IL, Cavanaugh CM (September 2005). "Chemosynthetic endosymbioses: adaptations to oxic-anoxic interfaces". Trends in Microbiology. 13 (9): 439–48. doi:10.1016/j.tim.2005.07.007. PMID 16054816.
  29. ^ Baker BJ, Lazar CS, Teske AP, Dick GJ (2015). "Genomic resolution of linkages in carbon, nitrogen, and sulfur cycling among widespread estuary sediment bacteria". Microbiome. 3: 14. doi:10.1186/s40168-015-0077-6. PMC 4411801. PMID 25922666.
  30. ^ Jannasch, H.W., andMottl, M.J. (1985). Geomicrobiology of deep-sea hydrothermal vents. Science 229, 717–725
  31. ^ Soixanteseize (2015-01-06). "Explore to understand, share to bring about change". Fondation Tara Océan. Retrieved 2020-11-22.
  32. ^ Han S, Li X, Luo X, Wen S, Chen W, Huang Q (2018). "Nitrite-Oxidizing Bacteria Community Composition and Diversity Are Influenced by Fertilizer Regimes, but Are Independent of the Soil Aggregate in Acidic Subtropical Red Soil". Frontiers in Microbiology. 9: 885. doi:10.3389/fmicb.2018.00885. PMC 5951965. PMID 29867799.
  33. ^ Cesar Mota, Jennifer Ridenoure, Jiayang Cheng, Francis L. de los Reyes, High levels of nitrifying bacteria in intermittently aerated reactors treating high ammonia wastewater. FEMS Microbiology Ecology, Volume 54, Issue 3, November 2005, pp. 391–400
  34. ^ Patwardhan S, Foustoukos DI, Giovannelli D, Yücel M, Vetriani C (2018). "Gammaproteobacteria During Colonization of a Shallow-Water Gas Vent". Frontiers in Microbiology. 9: 2970. doi:10.3389/fmicb.2018.02970. PMC 6291522. PMID 30574130.
  35. ^ Sabine Lenk, Julia Arnds, Katrice Zerjatke, Niculina Musat, Rudolf Amann and Marc Mußmann* Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany. Novel groups of Gammaproteobacteria catalyse sulfur oxidation and carbon fixation in a coastal, intertidal sediment. (2011)
  36. ^ Cho JC, Stapels MD, Morris RM, Vergin KL, Schwalbach MS, Givan SA, et al. (June 2007). "Polyphyletic photosynthetic reaction centre genes in oligotrophic marine Gammaproteobacteria". Environmental Microbiology. 9 (6): 1456–63. Bibcode:2007EnvMi...9.1456C. doi:10.1111/j.1462-2920.2007.01264.x. PMID 17504483.
  37. ^ Orata FD, Meier-Kolthoff JP, Sauvageau D, Stein LY (2018). "Methylococcales) Calls for the Reclassification of Members at the Genus and Species Levels". Frontiers in Microbiology. 9: 3162. doi:10.3389/fmicb.2018.03162. PMC 6315193. PMID 30631317.
  38. ^ a b Madigan, Michael T.; Jung, Deborah O. (2009). "An Overview of Purple Bacteria: Systematics, Physiology, and Habitats". In C. Neil Hunter; Fevzi Daldal; Marion C. Thurnauer; J. Thomas Beatty (eds.). The Purple Phototropic Bacteria. Advances in Photosynthesis and Respiration, vol. 28. Springer. pp. 1–15. doi:10.1007/978-1-4020-8815-5_1. ISBN 978-1-4020-8814-8. OL 25552439M.
  39. ^ Bryce C, Blackwell N, Schmidt C, Otte J, Huang YM, Kleindienst S, et al. (October 2018). "Microbial anaerobic Fe(II) oxidation - Ecology, mechanisms and environmental implications". Environmental Microbiology. 20 (10): 3462–3483. Bibcode:2018EnvMi..20.3462B. doi:10.1111/1462-2920.14328. PMID 30058270. S2CID 51865641.
  40. ^ Sabrina Hedrich, Michael Schlomann and D. Barrie Johnson. The iron-oxidizing proteobacteria. School of Biological Sciences, College of Natural Sciences, Bangor University, Deiniol Road, Bangor LL57 2UW, UK 2 Interdisciplinary Ecological Center, TU Bergakademie Freiberg, Leipziger Strasse 29, 09599 Freiberg, Germany. (2011)
  41. ^ Terry J. McGenity, Taxonomy, Genomics and Ecophysiology of Hydrocarbon-Degrading Microbes, 2019 143-152; 181-189; 191-205.
  42. ^ Markert S, Arndt C, Felbeck H, Becher D, Sievert SM, Hügler M, et al. (January 2007). "Physiological proteomics of the uncultured endosymbiont of Riftia pachyptila". Science. 315 (5809): 247–50. Bibcode:2007Sci...315..247M. doi:10.1126/science.1132913. hdl:1912/1514. PMID 17218528. S2CID 45745396.
  43. ^ Rubin-Blum M, Dubilier N, Kleiner M (January 2019). "Genetic Evidence for Two Carbon Fixation Pathways (the Calvin-Benson-Bassham Cycle and the Reverse Tricarboxylic Acid Cycle) in Symbiotic and Free-Living Bacteria". mSphere. 4 (1). doi:10.1128/mSphere.00394-18. PMC 6315080. PMID 30602523.
  44. ^ Karamipour N, Fathipour Y, Mehrabadi M (September 2016). "Gammaproteobacteria as essential primary symbionts in the striped shield bug, Graphosoma Lineatum (Hemiptera: Pentatomidae)". Scientific Reports. 6 (1): 33168. Bibcode:2016NatSR...633168K. doi:10.1038/srep33168. PMC 5016839. PMID 27609055.
  45. ^ Kikuchi Y, Hosokawa T, Nikoh N, Fukatsu T (February 2012). "Gut symbiotic bacteria in the cabbage bugs Eurydema rugosa and Eurydema dominulus (Heteroptera: Pentatomidae)". Applied Entomology and Zoology. 47 (1): 1–8. Bibcode:2012AppEZ..47....1K. doi:10.1007/s13355-011-0081-7. S2CID 14943700.
  46. ^ Tannenbaum I, Kaur J, Mann R, Sawbridge T, Rodoni B, Spangenberg G (August 2020). "Profiling the Lolium perenne microbiome: from seed to seed". Phytobiomes Journal. 4 (3): 281–9. doi:10.1094/PBIOMES-03-20-0026-R.
  47. ^ Breusing C, Schultz DT, Sudek S, Worden AZ, Young CR (September 2020). "High-contiguity genome assembly of the chemosynthetic gammaproteobacterial endosymbiont of the cold seep tubeworm Lamellibrachia barhami". Molecular Ecology Resources. 20 (5): 1432–44. doi:10.1111/1755-0998.13220. PMC 7540712.
  48. ^ Shiraishi A, Matsushita N, Hougetsu T (August 2010). "Nodulation in black locust by the Gammaproteobacteria Pseudomonas sp. and the Betaproteobacteria Burkholderia sp". Systematic and Applied Microbiology. 33 (5): 269–74. Bibcode:2010SyApM..33..269S. doi:10.1016/j.syapm.2010.04.005. PMID 20542651.
  49. ^ Ghosh PK, De TK, Maiti TK (2015-04-01). "Ascorbic acid production in root, nodule and Enterobacter spp. (Gammaproteobacteria) isolated from root nodule of the legume Abrus precatorius L.". Biocatalysis and Agricultural Biotechnology. 4 (2): 127–134. doi:10.1016/j.bcab.2014.11.006.
  50. ^ Benhizia Y, Benhizia H, Benguedouar A, Muresu R, Giacomini A, Squartini A (August 2004). "Gamma proteobacteria can nodulate legumes of the genus Hedysarum". Systematic and Applied Microbiology. 27 (4): 462–8. Bibcode:2004SyApM..27..462B. doi:10.1078/0723202041438527. PMID 15368852.
  51. ^ Nunoura T, Takaki Y, Kazama H, Kakuta J, Shimamura S, Makita H, et al. (2014-08-18). "Physiological and genomic features of a novel sulfur-oxidizing gammaproteobacterium belonging to a previously uncultivated symbiotic lineage isolated from a hydrothermal vent". PLOS ONE. 9 (8): e104959. Bibcode:2014PLoSO...9j4959N. doi:10.1371/journal.pone.0104959. PMC 4136832. PMID 25133584.
  52. ^ Holt JR (6 February 2013). "Description of the Phylum Gammaproteobacteria". Susquehanna University - Systematic Biology Course Website. Retrieved 17 April 2018.
  53. ^ Petersen JM, Ramette A, Lott C, Cambon-Bonavita MA, Zbinden M, Dubilier N (August 2010). "Dual symbiosis of the vent shrimp Rimicaris exoculata with filamentous gamma- and epsilonproteobacteria at four Mid-Atlantic Ridge hydrothermal vent fields". Environmental Microbiology. 12 (8): 2204–18. Bibcode:2010EnvMi..12.2204P. doi:10.1111/j.1462-2920.2009.02129.x. hdl:21.11116/0000-0001-CADC-4. PMID 21966914.
  54. ^ Shigenobu S, Watanabe H, Hattori M, Sakaki Y, Ishikawa H (September 2000). "Genome sequence of the endocellular bacterial symbiont of aphids Buchnera sp. APS". Nature. 407 (6800): 81–6. Bibcode:2000Natur.407...81S. doi:10.1038/35024074. PMID 10993077. S2CID 4405072.
  55. ^ Burke GR, Moran NA (2011). "Massive genomic decay in Serratia symbiotica, a recently evolved symbiont of aphids". Genome Biology and Evolution. 3: 195–208. doi:10.1093/gbe/evr002. PMC 3056288. PMID 21266540.
  56. ^ Evans FF, Egan S, Kjelleberg S (May 2008). "Ecology of type II secretion in marine gammaproteobacteria". Environmental Microbiology. 10 (5): 1101–7. Bibcode:2008EnvMi..10.1101E. doi:10.1111/j.1462-2920.2007.01545.x. PMID 18218035.
  57. ^ Baily JL, Foster G, Brown D, Davison NJ, Coia JE, Watson E, et al. (March 2016). "Salmonella infection in grey seals (Halichoerus grypus), a marine mammal sentinel species: pathogenicity and molecular typing of Salmonella strains compared with human and livestock isolates". Environmental Microbiology. 18 (3): 1078–87. Bibcode:2016EnvMi..18.1078B. doi:10.1111/1462-2920.13219. PMID 26768299.
  58. ^ Daniels NA, MacKinnon L, Bishop R, Altekruse S, Ray B, Hammond RM, Thompson S, Wilson S, Bean NH, Griffin PM, Slutsker L (May 2000). "Vibrio parahaemolyticus infections in the United States, 1973-1998". The Journal of Infectious Diseases. 181 (5): 1661–6. doi:10.1086/315459. PMID 10823766.