{"id":{"repo_id":"freiburg-diss","oai_identifier":"oai:freidok.uni-freiburg.de:648"},"canonical_url":"https://search.dev.ndltd.org/etd/freiburg-diss/oai:freidok.uni-freiburg.de:648","repository":{"repo_id":"freiburg-diss","name":"University of Freiburg","base_url":"https://freidok.uni-freiburg.de/oai/oai2.php"},"display":{"title":"Structural characterisation of V-ATPases by electron microscopy","abstract":"Vacuolar H+-translocating ATPases (V-ATPases) are fundamentally important proteins. They pump protons into the interior of most cellular endomembrane compartments at the expense of ATP. V-ATPases are comprised of a membrane-integrated proton-translocating part (V0) and a soluble catalytic part (V1). There are indications for multiple stalks connecting V1 and V0, however up to now three-dimensional information for a complete V-ATPase complex has not been available. <br>The V-ATPase was purified from three sources: lemon fruits, the plant Kalanchoë daigremontiana and the filamentous fungus Neurospora crassa. Structurally and functionally intact V-ATPases were obtained from K. daigremontiana and N. crassa. <br>The architecture of V-ATPase complexes was explored through electron microscopy of single particles and their subsequent digital image processing. Three-dimensional (3D) maps were calculated of the plant V-ATPase – both in the presence and the absence of a non-hydrolysable ATP analogue (AMP-PNP) – and the fungal V-ATPase. <br>In the 3D maps, the details of the three-dimensional organisation of the stalk region between V1 and V0 were revealed for the first time. They show that a central stalk is surrounded by three peripheral stalks of different sizes and shapes. These and previously established results were used to build a model of the subunit arrangement within the V-ATPase complex. Based on this model and the current understanding of the “rotor” mechanism in the closely related F-ATPases, it is possible to explain a similar rotor-stator-machinery in V-ATPases, thereby suggesting that three peripheral stalks form the static bearing. <br>From a regulatory point of view it was found that in the absence of the ATP analogue the V-ATPase was structurally less well defined, perhaps due to increased flexibility and partial detachment of some of the peripheral stalks. These structural changes might be the initial step in a controlled disassembly upon cellular ATP-depletion.","abstract_html":"Vacuolar H+-translocating ATPases (V-ATPases) are fundamentally important proteins. They pump protons into the interior of most cellular endomembrane compartments at the expense of ATP. V-ATPases are comprised of a membrane-integrated proton-translocating part (V0) and a soluble catalytic part (V1). There are indications for multiple stalks connecting V1 and V0, however up to now three-dimensional information for a complete V-ATPase complex has not been available. &lt;br&gt;The V-ATPase was purified from three sources: lemon fruits, the plant Kalanchoë daigremontiana and the filamentous fungus Neurospora crassa. Structurally and functionally intact V-ATPases were obtained from K. daigremontiana and N. crassa. &lt;br&gt;The architecture of V-ATPase complexes was explored through electron microscopy of single particles and their subsequent digital image processing. Three-dimensional (3D) maps were calculated of the plant V-ATPase – both in the presence and the absence of a non-hydrolysable ATP analogue (AMP-PNP) – and the fungal V-ATPase. &lt;br&gt;In the 3D maps, the details of the three-dimensional organisation of the stalk region between V1 and V0 were revealed for the first time. They show that a central stalk is surrounded by three peripheral stalks of different sizes and shapes. These and previously established results were used to build a model of the subunit arrangement within the V-ATPase complex. Based on this model and the current understanding of the “rotor” mechanism in the closely related F-ATPases, it is possible to explain a similar rotor-stator-machinery in V-ATPases, thereby suggesting that three peripheral stalks form the static bearing. &lt;br&gt;From a regulatory point of view it was found that in the absence of the ATP analogue the V-ATPase was structurally less well defined, perhaps due to increased flexibility and partial detachment of some of the peripheral stalks. These structural changes might be the initial step in a controlled disassembly upon cellular ATP-depletion.","abstract_has_math":false,"creators":["Domgall, Ines"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Gräber, Peter"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":null,"date_issued":"","date_published":null,"updated_at":"2026-07-24T02:21:52Z","subjects":["V-ATPase"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://freidok.uni-freiburg.de/data/648","outbound_label":"Repository record","outbound_source":"source_url"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Gräber, Peter"]},{"key":"dc:creator","label":"Author","values":["Domgall, Ines"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:type","label":"Dc Type","values":["DoctoralThesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["V-ATPase"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Vacuolar H+-translocating ATPases (V-ATPases) are fundamentally important proteins. They pump protons into the interior of most cellular endomembrane compartments at the expense of ATP. V-ATPases are comprised of a membrane-integrated proton-translocating part (V0) and a soluble catalytic part (V1). There are indications for multiple stalks connecting V1 and V0, however up to now three-dimensional information for a complete V-ATPase complex has not been available. <br>The V-ATPase was purified from three sources: lemon fruits, the plant Kalanchoë daigremontiana and the filamentous fungus Neurospora crassa. Structurally and functionally intact V-ATPases were obtained from K. daigremontiana and N. crassa. <br>The architecture of V-ATPase complexes was explored through electron microscopy of single particles and their subsequent digital image processing. Three-dimensional (3D) maps were calculated of the plant V-ATPase – both in the presence and the absence of a non-hydrolysable ATP analogue (AMP-PNP) – and the fungal V-ATPase. <br>In the 3D maps, the details of the three-dimensional organisation of the stalk region between V1 and V0 were revealed for the first time. They show that a central stalk is surrounded by three peripheral stalks of different sizes and shapes. These and previously established results were used to build a model of the subunit arrangement within the V-ATPase complex. Based on this model and the current understanding of the “rotor” mechanism in the closely related F-ATPases, it is possible to explain a similar rotor-stator-machinery in V-ATPases, thereby suggesting that three peripheral stalks form the static bearing. <br>From a regulatory point of view it was found that in the absence of the ATP analogue the V-ATPase was structurally less well defined, perhaps due to increased flexibility and partial detachment of some of the peripheral stalks. These structural changes might be the initial step in a controlled disassembly upon cellular ATP-depletion."]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Structural characterisation of V-ATPases by electron microscopy","Elektronenmikroskopische Charakterisierung von V-ATPasen"]}]}],"canonical_facts":{"dc:contributor":["Gräber, Peter"],"dc:creator":["Domgall, Ines"],"dc:description.abstract":["Vacuolar H+-translocating ATPases (V-ATPases) are fundamentally important proteins. They pump protons into the interior of most cellular endomembrane compartments at the expense of ATP. V-ATPases are comprised of a membrane-integrated proton-translocating part (V0) and a soluble catalytic part (V1). There are indications for multiple stalks connecting V1 and V0, however up to now three-dimensional information for a complete V-ATPase complex has not been available. <br>The V-ATPase was purified from three sources: lemon fruits, the plant Kalanchoë daigremontiana and the filamentous fungus Neurospora crassa. Structurally and functionally intact V-ATPases were obtained from K. daigremontiana and N. crassa. <br>The architecture of V-ATPase complexes was explored through electron microscopy of single particles and their subsequent digital image processing. Three-dimensional (3D) maps were calculated of the plant V-ATPase – both in the presence and the absence of a non-hydrolysable ATP analogue (AMP-PNP) – and the fungal V-ATPase. <br>In the 3D maps, the details of the three-dimensional organisation of the stalk region between V1 and V0 were revealed for the first time. They show that a central stalk is surrounded by three peripheral stalks of different sizes and shapes. These and previously established results were used to build a model of the subunit arrangement within the V-ATPase complex. Based on this model and the current understanding of the “rotor” mechanism in the closely related F-ATPases, it is possible to explain a similar rotor-stator-machinery in V-ATPases, thereby suggesting that three peripheral stalks form the static bearing. <br>From a regulatory point of view it was found that in the absence of the ATP analogue the V-ATPase was structurally less well defined, perhaps due to increased flexibility and partial detachment of some of the peripheral stalks. These structural changes might be the initial step in a controlled disassembly upon cellular ATP-depletion."],"dc:format.medium":["application/pdf"],"dc:subject":["V-ATPase"],"dc:title":["Structural characterisation of V-ATPases by electron microscopy","Elektronenmikroskopische Charakterisierung von V-ATPasen"],"dc:type":["DoctoralThesis"]},"updated_at":"2026-07-24T02:21:52Z"}