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- .ig XSRCH.TST VERS:- 01.00 DATE:- 09/26/86 TIME:- 09:37:59 PM
- .. Test file consisting of several CAS abstracts for use in trials of xsrchr
- .. (CAS abstracts are the default option if XSRCH.ZIP = XSRCHCAS.ZIP):
- ..
- .. Usage: xsrchr xsrch.tst +results_file
- .. [the program then enters full screen input -
- .. it is setup for condensing CAS files -
- .. enter ESC to continue]
- ..
- .. XSRCHR extracts condensed files like XMERGE1.TST, etc, from
- .. full abstract files.
- .. XSRCHR also can extract records satisfying specific search strings.
- *
- ANSWER 1 OF 5
-
- AN CA103(25):209170v
- TI Hydrogen-bonding networks in bacteriorhodopsin may afford a proton
- pathway and structural stability
- AU Rosenbusch, J. P.
- CS Eur. Mol. Biol. Lab.
- LO Heidelberg 6900, Fed. Rep. Ger.
- SO Bull. Inst. Pasteur (Paris), 83(3), 207-20
- SC 6-3 (General Biochemistry)
- DT J
- CO BIPAA8
- IS 0020-2452
- PY 1985
- LA Eng
- AB A structure of bacteriorhodopsin is proposed that may explain
- functional and structural properties which have not been previously
- accounted for. Its pattern is derived uniquely from the
- identification of turn regions as shown by C. Paul and J. P.
- Rosenbusch (1985). Significantly more polar and potentially ionized
- groups would be contained in the hydrophobic domain of the membrane
- than previously assumed, and would form extensive networks of H
- bonds. Criteria for residues which may contribute to proton
- conduction, combined with topol. considerations, suggest specific
- linear proton pathways that span the entire membrane in discrete
- steps. Two examples are presented, both of which comprise carboxyl
- and tyrosyl residues as pa⌠h≈ay π∩nstituents and include the
- retinal-linked lysine. The proximities of the groups involved as
- well as the very short helix-linking segments impose stringent topol.
- criteria. This allows probing of whether the proposed dense
- H-bonding systems could afford satn. of all donor and acceptor
- groups. Irresp. of detailed assignments, such satn. appears
- possible. H bonds within and between helixes could explain the
- unusual stability of bacteriorhodopsin and could also account for
- interactions between monomers, allowing their assocn. to purple
- membranes. Although this working hypothesis appears to offer
- plausible interpretations for several crit. properties of
- bacteriorhodopsin, it is likely to be as resistant to unequivocal
- proof as previously proposed models. Before the structure is known
- at at. resoln., however, the notion of extensive H bonding within
- hydrophobic domains in the protein and membrane interior may
- nonetheless refresh the concepts of the principles governing membrane
- protein structure.
- KW bacteriorhodopsin structure model function; hydrogen bond network
- bacteriorhodopsin; membrane protein hydrogen bond network
- IT Halobacterium halobium
- (bacteriorhodopsin of, hydrogen-bond network in, protein structure
- and function in relation to)
- IT Bacteriorhodopsins
- (hydrogen bond network in, hydrogen ion transport and monomer
- assocn. in relation to)
- IT Proteins
- (membranes, hydrogen-bond network in, structure and function at)
- IT Hydrogen bond
- (network, in bacteriorhodopsin, hydrogen ion transport and monomer
- assocn. in relation to)
- IT Conformation and Conformers
- Molecular structure, natural product
- (of bacteriorhodopsin, hydrogen-bond network in, membrane protein
- structure and function in relation to)
- IT Biological transport
- (of hydrogen ions, by bacteriorhodopsin, hydrogen-bond network in,
- membrane protein structure and function in relation to)
- IT 12408-02-5, biological studies
- (transport of, by bacteriorhodopsin, hydrogen-bond network in
- relation to)
-
- *
- ANSWER 2 OF 5
-
- AN CA102(5):41618a
- TI On the role of hydrogen bonds and hydrogen-bonded systems with large
- proton polarizability for mechanisms of proton activation and
- conduction in bacteriorhodopsin
- AU Zundel, G.; Merz, H.
- CS Inst. Phys. Chem., Univ. Munich
- LO Munich D-8000/2, Fed. Rep. Ger.
- SO Prog. Clin. Biol. Res., 164(Inf. Energy Transduction Biol. Membr.),
- 153-64
- SC 6-0 (General Biochemistry)
- SX 10
- DT J
- CO PCBRD2
- IS 0361-7742
- PY 1984
- LA Eng
- AB A review with 45 refs. H bonds and H-bonded chains with large proton
- polarizability are of decisive importance, both for the activation of
- protons and the conduction of the pos. charge in bacteriorhodopsin.
- KW review bacteriorhodopsin proton transfer hydrogen; hydrogen bond
- bacteriorhodopsin pump review
- IT Hydrogen bond
- (in proton transport by bacteriorhodopsin)
- IT Bacteriorhodopsins
- (proton transport in, hydrogen bonds and hydrogen-bonded systems
- in)
- IT 12408-02-5, biological studies
- (transport of, in bacteriorhodopsin, hydrogen bonds and
- hydrogen-bonded systems in)
-
- *
- ANSWER 3 OF 5
-
- AN CA97(23):194653m
- TI Light-induced aldimine bond migration as a possible mechanism for
- proton transfer in bacteriorhodopsin
- AU Ovchinnikov, Yu. A.; Abdulaev, N. G.
- CS Shemyakin Inst. Bioorg. Chem.
- LO Moscow 117988, USSR
- SO Membr. Transp., Volume 2, 319-22. Edited by: Martonosi, Anthony N.
- Plenum: New York, N. Y.
- SC 6-1 (General Biochemistry)
- DT C
- CO 48ETAH
- PY 1982
- LA Eng
- AB The light-driven proton-transporting mechanism of bacteriorhodopsin
- (BR) in membranes appears to involve proton-specific channels formed
- by chains of H bonds within the mol. This mechanism is supported by
- exptl. studies on aldimine bond migration occurring during the BR
- photocycle in which retinal covalently attached to the .epsilon.-NH2
- group of lysine-41 (Lys-41) in the dark migrates to Lys-215 on
- illumination. The protonation and deprotonation of retinal aldimines
- in different microenvironments of BR is advantageous for proton
- transport across the purple membrane.
- KW bacteriorhodopsin photocycle aldimine proton transport
- IT Light, biological effects
- (aldimine bond migration in bacteriorhodopsin induced by, hydrogen
- ion transport in relation to)
- IT Bacteriorhodopsins
- (aldimine bond migration in photocycle of, hydrogen ion transport
- in relation to)
- IT Hydrogen bond
- (of bacteriorhodopsin, photocycle effect on, hydrogen ion
- transport in relation to)
- IT Biological transport
- (of hydrogen ion, by purple membrane in bacteriorhodopsin
- photocycle, aldimine bond migration in relation to)
- IT Cell membrane
- (purple, bacteriorhodopsin hydrogen bonding in, photocycle effect
- on)
- IT 116-31-4
- (migration of, in bacteriorhodopsin photocycle, hydrogen ion
- transport in relation to)
- IT 12408-02-5, biological studies
- (transport of, by purple membrane in bacteriorhodopsin photocycle,
- aldimine bond migration in relation to)
-
- *
- ANSWER 4 OF 5
-
- AN CA95(19):164133h
- TI Proton conduction in bacteriorhodopsin via a hydrogen-bonded chain
- with large proton polarizability
- AU Merz, Helmut; Zundel, Georg
- CS Phys.-Chem. Inst., Univ. Muenchen
- LO Munich D-8000/2, Fed. Rep. Ger.
- SO Biochem. Biophys. Res. Commun., 101(2), 540-6
- SC 6-3 (General Biochemistry)
- DT J
- CO BBRCA9
- IS 0006-291X
- PY 1981
- LA Eng
- AB A Corey-Pauling-Kolthun mol. model of bacteriorhodopsin was built.
- This model shows that a largely structurally sym. H-bonded chain
- Asp-Tyr-Tyr-Tyr-Tyr-Tyr-Tyr-Glu may be formed. With regard to the
- total proton potential this chain shows very large proton
- polarizability and thus via this chain the pos. charge can be
- conducted to the outside of the membrane via a Grotthus mechanism.
- KW bacteriorhodopsin proton transport hydrogen bond
- IT Bacteriorhodopsins
- (hydrogen ion transport by, hydrogen-bonded peptide chain in
- relation to)
- IT Hydrogen bond
- (of peptide chain, of bacteriorhodopsin, hydrogen ion transport in
- relation to)
- IT 12408-02-5, biological studies
- (transport of, in bacteriorhodopsin, hydrogen-bonded peptide chain
- in relation to)
-
- *
- ANSWER 5 OF 5
-
- AN CA94(15):116126r
- TI Molecular models of proton pumps
- AU Nagle, J. F.; Mille, M.
- CS Dep. Phys., Carnegie-Mellon Univ.
- LO Pittsburgh, PA 15213, USA
- SO J. Chem. Phys., 74(2), 1367-72
- SC 6-1 (General Biochemistry)
- DT J
- CO JCPSA6
- IS 0021-9606
- PY 1981
- LA Eng
- AB Three theor. models of proton pumps are discussed at the mol. level.
- The models contain H bonded chains, which are the best understood
- channels, structurally and kinetically, for proton conduction within
- membranes. The 1st model, called the integral injector model, has an
- active site which involves a pK change. The 2nd model, called the
- switch model, utilizes a conformational change in a retinal as the
- active site. The 3rd model, called the active chain model, involves
- a conformational change in the protein, and the active site is
- delocalized to include the entire H-bonded chain. The models
- presented were chosen in part because of their possible relevance to
- the bacteriorhodopsin proton pump and are compared with this system,
- but the basic principles involved have greater generality. They were
- chosen to explore the general family of theor. proton pumps. Each
- model illustrates general principles that form a basis for generating
- addnl. models in the family.
- KW proton pump membrane model; bacteriorhodopsin proton pump model
- IT Chains, chemical
- (conformational transitions of, of proton pump protein,
- mechanistic model in relation to)
- IT Hydrogen bond
- (in proton pump models)
- IT Biological transport
- (of hydrogen ion, mechanism of, model of)
- IT Conformational inversion
- (of retinal, proton pump mechanism in relation to)
- IT Bacteriorhodopsins
- (proton transport by, mechanism of, models of)
- IT Membranes and Diaphragms
- (biol., proton transport by, mechanism of, models of)
- IT 12408-02-5, biological studies
- (transport of, model of)
-