Adventurous motility is as a type of gliding motility; unlike most motility mechanisms, adventurous motility does not involve a flagellum. Gliding motility usually involves swarms of bacteria; however, adventurous motility is practiced by individual cells.[1] This gliding is hypothesized to occur via assembly of a type IV secretion system and the extrusion of a polysaccharide slime,[2] or by use of a series of adhesion complexes. The majority of research on adventurous motility has focused on the species, Myxococcus xanthus. The earliest of this research is attributed to Jonathan Hodgkin and Dale Kaiser.
There are currently two leading hypotheses explaining how adventurous motility occurs: (1) polar expulsion of slime or (2) a currently unknown motor that makes use of cell surface adhesion proteins.[3] These methods of movement may coordinate with one another. The adhesion proteins may allow the cell to move across the substrate, while the slime propulsion system aids in lubrication.[4]
Myxococcus has been observed leaving a slime trail on agar.[5] This is thought to contribute to the gliding motility of these cells. As slime is expelled out of one of the poles, the bacterium is propelled forward. An experiment was performed by Rosa Yu and Dale Kaiser to support this claim. A transposon insertion mutation was added to bacteria which were capable of adventurous motility. In fifteen of the thirty-three bacteria, the cells started to expel slime from both poles simultaneously. These bacteria were unable to move forwards or backwards.[5] The remaining bacteria were still able to move via a polar slime propulsion system; however, the efficacy of the movement was decreased.[5] This supports the hypothesis that these cells experience adventurous motility through the use of slime expulsion. Nozzle-like organelles responsible for this propulsion have been identified in Phormidium species of cyanobacteria.[6] It is thought that these nozzle-like organelles may be present in Myxococcus species. Mathematical models have shown that these nozzles can generate enough force to move bacterial species in the same manner that they are observed moving.[7]
Myxococcus has also been observed moving via the use of surface adhesion complexes.[8] These complexes stay in a fixed position relative to the substrate as the cell moves. The adhesion proteins are assembled at the leading pole of the cell, and disassembled at the trailing end of the cell. The entirety of the cell then travels along this mechanism of adhesion/disassembly. These complexes were found through the fluorescence and observation of the AglZ-YFP protein.[3] As the cell moved forward, this protein was found to be associated with the substrate at a fixed position. It has been proposed that this is the result of a currently uncharacterized protein motor. This motor would attach to these "focal adhesion complexes," and move the cell forward through its gliding motility.[3] This finding is in direct contradiction of hypothesis (1); these adhesion proteins exist along the length of the cell, while the expulsion of slime and its associated nozzle-like organelle exists at the poles of the cell.
Frz and AglZ interactionsedit
Both motility systems' reversals (S and A) are controlled by the Frz chemosensory pathway. An N-terminal pseudo-receiver domain and a lengthy C-terminal coiled-coil domain are both present in the cytoplasmic protein known as AglZ which interacts with FrzCD, the receptor for the Frz pathway. This interaction is likely to occur through their N-terminal regions. Studies of in vitro protein cross-linking was done to determine this finding.[9] The presence of focal adhesion complexes driving cell movement during adventurous motility is suggested by the localization of AglZ in clusters that stay stable with respect to the substrate as cells advance. Mutant findings demonstrated that AglZ is a regulator of the A-motility system rather than a part of the engine driving A-motility. "As cells reverse, they both switch polarity in a coordinated manner."[9] AglZ and FrzS have been postulated to be positioned downstream of the Frz pathway in the control of A- and S-motility, respectively. Genetic studies overwhelmingly support the notion that AglZ is upstream of the Frz pathway.
Myxococcus xanthusedit
M. xanthus Fruiting Bodies are macroscopic and visible to the naked eye.
M. xanthus is a member of the Proteobacteria phylum, and is classified therein as a Deltaproteobacteria. The name Myxococcus xanthus can be interpreted as "yellow slime coccus".[10] When examined under the microscope it appears as a Gram-negative rod, and is noted for its ability to form spores and fruiting bodies. M. xanthus is the primary example, and most researched microbe that takes part in adventurous motility. Commonly found in the soil, M. xanthus is capable of moving across solid surfaces without the use of flagella. This is achieved through two different methods of motility - social motility and adventurous motility.[11]M. xanthus preys on other bacterial cells, and uses social motility and adventurous motility to hunt in packs or individually respectively.[10]
Structural makeupedit
Studies have shown that adventurous motility is made up of 21 genetic loci and two different structures. The two structures we have identified is a secretion organelle and a linear periodic chain like structure.[4] Adventurous motility is not fully understood but it is proposed that Agl/Glt proteins form a large envelope that then interacts with MreB filaments. This interaction then allows it to move across the cytoplasmic membrane. The slime component of adventurous motility has been thought to assist in lubrication, adhesion, propulsion, and also decrease friction.[4]
Historyedit
This image depicts a variety of types of bacterial locomotion
Since microorganisms began inhabiting the Earth 3.7 billion years ago, differing forms of motility have developed over time. Motility allows bacteria to move toward food and more favorable environments, or away from toxins. A deeper investigation into gliding motility began in the 1970's at the hands of Hodgkin and Kaiser. Through genetic analysis, they were able to find two distinct subsets of genes that contribute to the motility of Myxococcusxanthus. These genes result in a sort of "social motility" which allows the microbes to hunt in packs.[2] Adventurous motility can also be described as an individual cell exploring a territory. This exploring movement is possible through a mix of slime secretion, motor proteins, and focal adhesion complexes.[12] Social motility and adventurous motility are both considered mutations and are the topic of many studies as they are not well understood.[9]Myxococcus xanthus has been the most researched bacterium in regards to adventurous motility.[2]
Referencesedit
^McBride, Mark J. (31 January 1996). "Behavioral analysis of single cells of Myxococcus xanthus in response to prey cells of Escherichia coli". FEMS Microbiology Letters. 137 (2–3): 227–331. doi:10.1016/0378-1097(96)00062-6. PMID 8998990.
^ abcYouderian, Philip (1998-06-04). "Bacterial motility: Secretory secrets of gliding bacteria". Current Biology. 8 (12): R408–R411. doi:10.1016/S0960-9822(98)70264-7. ISSN 0960-9822. PMID 9637910. S2CID 14847666.
^ abcSliusarenko, Oleksii; Zusman, David R.; Oster, George (November 2007). "The Motors Powering A-Motility in Myxococcus xanthus Are Distributed along the Cell Body". Journal of Bacteriology. 189 (21): 7920–7921. doi:10.1128/JB.00923-07. ISSN 0021-9193. PMC2168729. PMID 17704221.
^ abcKoch, Matthias K.; Hoiczyk, Egbert (September 2013). "Characterization of myxobacterial A-motility: insights from microcinematographic observations". Journal of Basic Microbiology. 53 (9): 785–791. doi:10.1002/jobm.201200307. ISSN 0233-111X. PMC4160302. PMID 23322594.
^Hoiczyk, Egbert; Baumeister, Wolfgang (1998-10-22). "The junctional pore complex, a prokaryotic secretion organelle, is the molecular motor underlying gliding motility in cyanobacteria". Current Biology. 8 (21): 1161–1168. doi:10.1016/S0960-9822(07)00487-3. ISSN 0960-9822. PMID 9799733. S2CID 14384308.
^Youderian, Philip; Burke, Neal; White, David J.; Hartzell, Patricia L. (2003-06-17). "Identification of genes required for adventurous gliding motility in Myxococcus xanthus with the transposable element mariner: Gliding motility genes". Molecular Microbiology. 49 (2): 555–570. doi:10.1046/j.1365-2958.2003.03582.x. PMID 12828649. S2CID 20217855.
^Mignot, Tâm; Shaevitz, Joshua W.; Hartzell, Patricia L.; Zusman, David R. (2007-02-09). "Evidence that focal adhesion complexes power bacterial gliding motility". Science. 315 (5813): 853–856. Bibcode:2007Sci...315..853M. doi:10.1126/science.1137223. ISSN 1095-9203. PMC4095873. PMID 17289998.
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adventurous, motility, this, article, technical, most, readers, understand, please, help, improve, make, understandable, experts, without, removing, technical, details, october, 2022, learn, when, remove, this, message, type, gliding, motility, unlike, most, m. This article may be too technical for most readers to understand Please help improve it to make it understandable to non experts without removing the technical details October 2022 Learn how and when to remove this message Adventurous motility is as a type of gliding motility unlike most motility mechanisms adventurous motility does not involve a flagellum Gliding motility usually involves swarms of bacteria however adventurous motility is practiced by individual cells 1 This gliding is hypothesized to occur via assembly of a type IV secretion system and the extrusion of a polysaccharide slime 2 or by use of a series of adhesion complexes The majority of research on adventurous motility has focused on the species Myxococcus xanthus The earliest of this research is attributed to Jonathan Hodgkin and Dale Kaiser Myxococcus xanthus visualized under a microscope Contents 1 Competing hypotheses 2 Frz and AglZ interactions 3 Myxococcus xanthus 4 Structural makeup 5 History 6 ReferencesCompeting hypotheses editThere are currently two leading hypotheses explaining how adventurous motility occurs 1 polar expulsion of slime or 2 a currently unknown motor that makes use of cell surface adhesion proteins 3 These methods of movement may coordinate with one another The adhesion proteins may allow the cell to move across the substrate while the slime propulsion system aids in lubrication 4 Myxococcus has been observed leaving a slime trail on agar 5 This is thought to contribute to the gliding motility of these cells As slime is expelled out of one of the poles the bacterium is propelled forward An experiment was performed by Rosa Yu and Dale Kaiser to support this claim A transposon insertion mutation was added to bacteria which were capable of adventurous motility In fifteen of the thirty three bacteria the cells started to expel slime from both poles simultaneously These bacteria were unable to move forwards or backwards 5 The remaining bacteria were still able to move via a polar slime propulsion system however the efficacy of the movement was decreased 5 This supports the hypothesis that these cells experience adventurous motility through the use of slime expulsion Nozzle like organelles responsible for this propulsion have been identified in Phormidium species of cyanobacteria 6 It is thought that these nozzle like organelles may be present in Myxococcus species Mathematical models have shown that these nozzles can generate enough force to move bacterial species in the same manner that they are observed moving 7 Myxococcus has also been observed moving via the use of surface adhesion complexes 8 These complexes stay in a fixed position relative to the substrate as the cell moves The adhesion proteins are assembled at the leading pole of the cell and disassembled at the trailing end of the cell The entirety of the cell then travels along this mechanism of adhesion disassembly These complexes were found through the fluorescence and observation of the AglZ YFP protein 3 As the cell moved forward this protein was found to be associated with the substrate at a fixed position It has been proposed that this is the result of a currently uncharacterized protein motor This motor would attach to these focal adhesion complexes and move the cell forward through its gliding motility 3 This finding is in direct contradiction of hypothesis 1 these adhesion proteins exist along the length of the cell while the expulsion of slime and its associated nozzle like organelle exists at the poles of the cell Frz and AglZ interactions editBoth motility systems reversals S and A are controlled by the Frz chemosensory pathway An N terminal pseudo receiver domain and a lengthy C terminal coiled coil domain are both present in the cytoplasmic protein known as AglZ which interacts with FrzCD the receptor for the Frz pathway This interaction is likely to occur through their N terminal regions Studies of in vitro protein cross linking was done to determine this finding 9 The presence of focal adhesion complexes driving cell movement during adventurous motility is suggested by the localization of AglZ in clusters that stay stable with respect to the substrate as cells advance Mutant findings demonstrated that AglZ is a regulator of the A motility system rather than a part of the engine driving A motility As cells reverse they both switch polarity in a coordinated manner 9 AglZ and FrzS have been postulated to be positioned downstream of the Frz pathway in the control of A and S motility respectively Genetic studies overwhelmingly support the notion that AglZ is upstream of the Frz pathway Myxococcus xanthus edit nbsp M xanthus Fruiting Bodies are macroscopic and visible to the naked eye M xanthus is a member of the Proteobacteria phylum and is classified therein as a Deltaproteobacteria The name Myxococcus xanthus can be interpreted as yellow slime coccus 10 When examined under the microscope it appears as a Gram negative rod and is noted for its ability to form spores and fruiting bodies M xanthus is the primary example and most researched microbe that takes part in adventurous motility Commonly found in the soil M xanthus is capable of moving across solid surfaces without the use of flagella This is achieved through two different methods of motility social motility and adventurous motility 11 M xanthus preys on other bacterial cells and uses social motility and adventurous motility to hunt in packs or individually respectively 10 Structural makeup editStudies have shown that adventurous motility is made up of 21 genetic loci and two different structures The two structures we have identified is a secretion organelle and a linear periodic chain like structure 4 Adventurous motility is not fully understood but it is proposed that Agl Glt proteins form a large envelope that then interacts with MreB filaments This interaction then allows it to move across the cytoplasmic membrane The slime component of adventurous motility has been thought to assist in lubrication adhesion propulsion and also decrease friction 4 History edit nbsp This image depicts a variety of types of bacterial locomotion Since microorganisms began inhabiting the Earth 3 7 billion years ago differing forms of motility have developed over time Motility allows bacteria to move toward food and more favorable environments or away from toxins A deeper investigation into gliding motility began in the 1970 s at the hands of Hodgkin and Kaiser Through genetic analysis they were able to find two distinct subsets of genes that contribute to the motility of Myxococcus xanthus These genes result in a sort of social motility which allows the microbes to hunt in packs 2 Adventurous motility can also be described as an individual cell exploring a territory This exploring movement is possible through a mix of slime secretion motor proteins and focal adhesion complexes 12 Social motility and adventurous motility are both considered mutations and are the topic of many studies as they are not well understood 9 Myxococcus xanthus has been the most researched bacterium in regards to adventurous motility 2 References edit McBride Mark J 31 January 1996 Behavioral analysis of single cells of Myxococcus xanthus in response to prey cells of Escherichia coli FEMS Microbiology Letters 137 2 3 227 331 doi 10 1016 0378 1097 96 00062 6 PMID 8998990 a b c Youderian Philip 1998 06 04 Bacterial motility Secretory secrets of gliding bacteria Current Biology 8 12 R408 R411 doi 10 1016 S0960 9822 98 70264 7 ISSN 0960 9822 PMID 9637910 S2CID 14847666 a b c Sliusarenko Oleksii Zusman David R Oster George November 2007 The Motors Powering A Motility in Myxococcus xanthus Are Distributed along the Cell Body Journal of Bacteriology 189 21 7920 7921 doi 10 1128 JB 00923 07 ISSN 0021 9193 PMC 2168729 PMID 17704221 a b c Koch Matthias K Hoiczyk Egbert September 2013 Characterization of myxobacterial A motility insights from microcinematographic observations Journal of Basic Microbiology 53 9 785 791 doi 10 1002 jobm 201200307 ISSN 0233 111X PMC 4160302 PMID 23322594 a b c Yu Rosa Kaiser Dale January 2007 Gliding motility and polarized slime secretion Gliding motility and polarized slime secretion Molecular Microbiology 63 2 454 467 doi 10 1111 j 1365 2958 2006 05536 x PMID 17176257 S2CID 41595243 Hoiczyk Egbert Baumeister Wolfgang 1998 10 22 The junctional pore complex a prokaryotic secretion organelle is the molecular motor underlying gliding motility in cyanobacteria Current Biology 8 21 1161 1168 doi 10 1016 S0960 9822 07 00487 3 ISSN 0960 9822 PMID 9799733 S2CID 14384308 Wolgemuth Charles Hoiczyk Egbert Kaiser Dale Oster George 2002 03 05 How Myxobacteria Glide Current Biology 12 5 369 377 doi 10 1016 S0960 9822 02 00716 9 ISSN 0960 9822 PMID 11882287 S2CID 2881449 Mignot Tam Shaevitz Joshua W Hartzell Patricia L Zusman David R 2007 02 09 Evidence That Focal Adhesion Complexes Power Bacterial Gliding Motility Science 315 5813 853 856 Bibcode 2007Sci 315 853M doi 10 1126 science 1137223 ISSN 0036 8075 PMC 4095873 PMID 17289998 a b c Mauriello Emilia M F Nan Beiyan Zusman David R May 2009 AglZ regulates adventurous A motility in Myxococcus xanthus through its interaction with the cytoplasmic receptor FrzCD Molecular Microbiology 72 4 964 977 doi 10 1111 j 1365 2958 2009 06697 x ISSN 0950 382X PMC 4098657 PMID 19400788 a b Vos Michiel 2021 Myxococcus xanthus Trends in Microbiology 29 6 562 563 doi 10 1016 j tim 2021 03 006 hdl 10871 126015 PMID 33795155 S2CID 232762785 Retrieved 2022 10 07 Youderian Philip Burke Neal White David J Hartzell Patricia L 2003 06 17 Identification of genes required for adventurous gliding motility in Myxococcus xanthus with the transposable element mariner Gliding motility genes Molecular Microbiology 49 2 555 570 doi 10 1046 j 1365 2958 2003 03582 x PMID 12828649 S2CID 20217855 Mignot Tam Shaevitz Joshua W Hartzell Patricia L Zusman David R 2007 02 09 Evidence that focal adhesion complexes power bacterial gliding motility Science 315 5813 853 856 Bibcode 2007Sci 315 853M doi 10 1126 science 1137223 ISSN 1095 9203 PMC 4095873 PMID 17289998 This article needs additional or more specific categories Please help out by adding categories to it so that it can be listed with similar articles October 2022 Retrieved from https en wikipedia org w index php title Adventurous motility amp oldid 1167033195, wikipedia, wiki, book, books, library,
