ABC-type maltose transporter / ABC-type maltose transporter activity / negative regulation of maltose transport / enzyme IIA-maltose transporter complex / negative regulation of transmembrane transport / maltose transport complex / maltose transport / maltodextrin transmembrane transport / ATP-binding cassette (ABC) transporter complex, substrate-binding subunit-containing / ATP-binding cassette (ABC) transporter complex ...ABC-type maltose transporter / ABC-type maltose transporter activity / negative regulation of maltose transport / enzyme IIA-maltose transporter complex / negative regulation of transmembrane transport / maltose transport complex / maltose transport / maltodextrin transmembrane transport / ATP-binding cassette (ABC) transporter complex, substrate-binding subunit-containing / ATP-binding cassette (ABC) transporter complex / DNA-binding transcription factor binding / DNA damage response / ATP hydrolysis activity / ATP binding / membrane / plasma membrane 類似検索 - 分子機能
Maltose transport system permease protein MalF, P2 domain / MalF, N-terminal / : / : / Maltose transport system permease protein MalF P2 domain / MalF, N-terminal region, transmembrane helices / Maltose/Maltodextrin import ATP-binding protein malK family profile. / Transport-associated OB, type 2 / TOBE domain / ABC transporter, maltose/maltodextrin import, MalK-like ...Maltose transport system permease protein MalF, P2 domain / MalF, N-terminal / : / : / Maltose transport system permease protein MalF P2 domain / MalF, N-terminal region, transmembrane helices / Maltose/Maltodextrin import ATP-binding protein malK family profile. / Transport-associated OB, type 2 / TOBE domain / ABC transporter, maltose/maltodextrin import, MalK-like / : / Molybdate/tungstate binding, C-terminal / ABC transporter type 1, transmembrane domain MetI-like / MetI-like superfamily / Binding-protein-dependent transport system inner membrane component / ABC transporter integral membrane type-1 domain profile. / ABC transporter-like, conserved site / ABC transporters family signature. / ABC transporter / ABC transporter-like, ATP-binding domain / ATP-binding cassette, ABC transporter-type domain profile. / ATPases associated with a variety of cellular activities / AAA+ ATPase domain / Nucleic acid-binding, OB-fold / P-loop containing nucleoside triphosphate hydrolase 類似検索 - ドメイン・相同性
Maltose/maltodextrin transport system permease protein MalF / Maltose/maltodextrin transport system permease protein MalG / Maltose/maltodextrin import ATP-binding protein MalK 類似検索 - 構成要素
ジャーナル: J Biol Chem / 年: 2017 タイトル: Negative Stain Single-particle EM of the Maltose Transporter in Nanodiscs Reveals Asymmetric Closure of MalK and Catalytic Roles of ATP, MalE, and Maltose. 著者: Lucien Fabre / Huan Bao / James Innes / Franck Duong / Isabelle Rouiller / 要旨: The MalE-MalFGK complex is one of the best characterized members of the large and ubiquitous family of ATP-binding cassette (ABC) transporters. It is composed of a membrane-spanning heterodimer, ...The MalE-MalFGK complex is one of the best characterized members of the large and ubiquitous family of ATP-binding cassette (ABC) transporters. It is composed of a membrane-spanning heterodimer, MalF-MalG; a homodimeric ATPase, MalK; and a periplasmic maltose receptor, MalE. Opening and closure of MalK is coupled to conformational changes in MalF-MalG and the alternate exposition of the substrate-binding site to either side of the membrane. To further define this alternate access mechanism and the impact of ATP, MalE, and maltose on the conformation of the transporter during the transport cycle, we have reconstituted MalFGK in nanodiscs and analyzed its conformations under 10 different biochemical conditions using negative stain single-particle EM. EM map results (at 15-25 Å resolution) indicate that binding of ATP to MalK promotes an asymmetric, semi-closed conformation in accordance with the low ATPase activity of MalFGK In the presence of MalE, the MalK dimer becomes fully closed, gaining the ability to hydrolyze ATP. In the presence of ADP or maltose, MalE·MalFGK remains essentially in a semi-closed symmetric conformation, indicating that release of these ligands is required for the return to the initial state. Taken together, this structural information provides a rationale for the stimulation of MalK ATPase activity by MalE as well as by maltose.
MalFGK2 reconstituted in nanodiscs at a molar ratio MalFGK2:MSP1D1:lipid (DOPC)of 1:3:60. MalE cross-linked to MalFGK2. Complex incubated with maltose.
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電子顕微鏡法
顕微鏡
FEI TECNAI F20
撮影
フィルム・検出器のモデル: GATAN ULTRASCAN 4000 (4k x 4k) 平均電子線量: 20.0 e/Å2