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1.
Ch. Richter 《Cellular and molecular life sciences : CMLS》1977,33(7):860-862
Summary The participation of highly energetic oxygen species in the ATP-induced bioluminescence of a firefly-extract has been investigated. The inhibition of light emission by a variety of specific scavengers suggests that singlet oxygen, superoxide radicals and hydroxyl radicals are important intermediates in the firefly bioluminescence reaction.Acknowledgments. I thank Prof. R. Bachofen, Institut für Allgemeine Botanik, Abteilung Mikrobiologie, Universität Zürich, Switzerland, in whose laboratory most of these studies have been performed, for his cooperativity. Financial support by the Deutsche Studienstiftung is gratefully acknowledged. 相似文献
2.
Hosseinkhani S 《Cellular and molecular life sciences : CMLS》2011,68(7):1167-1182
Firefly luciferase-catalyzed reaction proceeds via the initial formation of an enzyme-bound luciferyl adenylate intermediate.
The chemical origin of the color modulation in firefly bioluminescence has not been understood until recently. The presence
of the same luciferin molecule, in combination with various mutated forms of luciferase, can emit light at slightly different
wavelengths, ranging from red to yellow to green. A historical perspective of development in understanding of color emission
mechanism is presented. To explain the variation in the color of the bioluminescence, different factors have been discussed
and five hypotheses proposed for firefly bioluminescence color. On the basis of recent results, light-color modulation mechanism
of firefly luciferase propose that the light emitter is the excited singlet state of OL− [1(OL−)*], and light emission from 1(OL−)* is modulated by the polarity of the active-site environment at the phenol/phenolate terminal of the benzothiazole fragment
in oxyluciferin. 相似文献
3.
Di Francesco AM Ruggiero A Riccardi R 《Cellular and molecular life sciences : CMLS》2002,59(11):1914-1927
Oxaliplatin (Eloxatine) is a third-generation platinum compound which has shown a wide antitumour effect both in vitro and
in vivo, a better safety profile than cisplatin and a lack of cross-resistance with cisplatin and carboplatin. In this scenario,
oxaliplatin may represent an innovative and challenging drug extending the antitumour activity in diseases such as gastrointestinal
cancer that are not usually sensitive to these coordination complexes. Oxaliplatin has a non-hydrolysable diaminocyclohexane
(DACH) carrier ligand which is maintained in the final cytotoxic metabolites of the drug. Like cisplatin, oxaliplatin targets
DNA producing mainly 1,2-GG intrastrand cross-links. The cellular and molecular aspects of the mechanism of action of oxaliplatin
have not yet been fully elucidated. However, the intrinsic chemical and steric characteristics of the DACH-platinum adducts
appear to contribute to the lack of cross-resistance with cisplatin. To date, mismatch repair and replicative bypass appear
to be the processes most likely involved in differentiating the molecular responses to these agents.
Received 15 March 2002; received after revision 13 May 2002; accepted 21 May 2002
RID="*"
ID="*"Corresponding author. 相似文献
4.
5.
Satoshi Inouye 《Cellular and molecular life sciences : CMLS》2010,67(3):387-404
Firefly luciferase is a member of the acyl-adenylate/thioester-forming superfamily of enzymes and catalyzes the oxidation
of firefly luciferin with molecular oxygen to emit light. Knowledge of the luminescence mechanism catalyzed by firefly luciferase
has been gathered, leading to the discovery of a novel catalytic function of luciferase. Recently, we demonstrated that firefly
luciferase has a catalytic function of fatty acyl-CoA synthesis from fatty acids in the presence of ATP, Mg2+ and coenzyme A. Based on identification of fatty acyl-CoA genes in firefly, Drosophila, and non-luminous click beetles, we then proposed that the evolutionary origin of firefly luciferase is a fatty acyl-CoA
synthetase in insects. Further, we succeeded in converting the fatty acyl-CoA synthetase of non-luminous insects into functional
luciferase showing luminescence activity by site-directed mutagenesis. 相似文献
6.
7.
The modular nature of apoptotic signaling proteins 总被引:9,自引:0,他引:9
K. Hofmann 《Cellular and molecular life sciences : CMLS》1999,55(8-9):1113-1128
Apoptosis, initiated by a variety of stimuli, is a physiological process that engages a well-ordered signaling cascade, eventually
leading to the controlled death of the cell. The most extensively studied apoptotic stimulus is the binding of death receptors
related to CD95 (Fas/Apo1) by their respective ligands. During the last years, a considerable number of proteins have been
identified which act together in the receptor-proximal part of the signaling pathway. Based on localized regions of sequence
similarity, it has been predicted that these proteins consist of several independently folding domains. In several cases these
predictions have been confirmed by structural studies; in other cases they are at least supported by experimental data. This
review focuses on the three most widespread domain families found in the apoptotic signaling proteins: the death domain, the
death effector domain and the caspase recruitment domain. The recently discovered analogies between these domains, both in
structure and in function, have shed some light on the overall architecture of the pathway leading from death receptor ligation
to the activation of caspases and eventually to the apoptotic phenotype.
Received 8 October 1998; received after revision 8 January 1999; accepted 8 January 1999 相似文献
8.
The role of thrombospondin-1 in apoptosis 总被引:3,自引:0,他引:3
The thrombospondins are a family of extracellular proteins that participate in cell-to-cell and cell-to-matrix communication.
They regulate cellular phenotype during tissue genesis and repair. Five family members, each representing a separate gene
product, probably exist in most vertebrate species. Like most extracellular proteins, the thrombospondins are composed of
several structural domains that are responsible for the numerous biological functions that have been described for this protein
family. Considerable progress has been made towards understanding the function of thrombospondins. The role of thrombospondin
in the process of apoptosis or programmed cell death has recently come into focus. In this review we will concentrate on the
role of thrombospondin-1 in the broad field of apoptotis research.
Received 5 December 2001; received after revision 28 March 2002; accepted 28 March 2002 相似文献
9.
Neurotrophins are a family of structurally and functionally related neurotrophic factors which, in mammals, include: nerve
growth factor, brain-derived neurotrophic factor, neurotrophin-3 (NT-3), and NT-4/5. In addition to their canonical role in
promoting neuronal survival, these molecules appear to regulate multiple aspects of the development of the nervous system
in vertebrates, including neuronal differentiation, axon elongation and target innervation, among others. Actions of neurotrophins
and of their receptors in vivo are being analyzed by loss-of-function or gain-of-function experiments in mice. Here, we review
the phenotypes of the primary sensory system in these mutant mouse strains and the different strategies specifically involved
in the regulation of neuronal survival by neurotrophins in this portion of the nervous system.
Received 10 December 2001; received after revision 11 May 2002; accepted 13 May 2002
RID="*"
ID="*"Corresponding author. 相似文献
10.
B. Zhivotovsky D. H. Burgess S. Orrenius 《Cellular and molecular life sciences : CMLS》1996,52(10-11):968-978
The interleukin-1 β-converting enzyme (ICE)-like family proteases have recently been identified as key enzymes in apoptotic cell death. Among these proteases one can identify specific activities which may be involved in cytokine production or in resident protein cleavage. Several factors influence the constitutive apoptotic mechanism and may provide insight into the role of protease(s) in apoptosis. Although it appears that ICE family members play a most important role in promoting apoptotic cell death, evidence has been advanced that other proteases are also involved in sequential or parallel steps of apoptosis. Activation of a particular protease can lead to processing molecules either of the same or different proteases, leading to an activation of a protease cascade. Here we attempt to summarize the current thinking concerning these proteases and their involvement in apoptosis. 相似文献
11.
Prosperi-Meys C de Seny D Llabres G Galleni M Lamotte-Brasseur J 《Cellular and molecular life sciences : CMLS》2002,59(12):2136-2143
Increased resistance to β-lactam antibiotics is mainly due to β-lactamases. X-ray structures of zinc β-lactamases unraveled
the coordination of the metal ions, but their mode of action remains unclear. Recently, enzymes in which one of the zinc ligands
was mutated have been characterized and their catalytic activity against several β-lactam antibiotics measured. A molecular
modeling study of these enzymes was performed here to explain the catalytic activity of the mutants. Coordination around the
zinc ions influences the way the tetrahedral intermediate is bound; any modification influences the first recognition of the
substrate by the enzyme. For all the studied mutants, at least one of the interactions fails, inducing a loss of catalytic
efficiency compared to the wild type. The present studies show that the enzyme cavity is a structure of high plasticity both
structurally and mechanistically and that local modifications may propagate its effects far from the mutated amino
acid.
Received 28 August 2002; received after revision 22 October 2002; accepted 24 October 2002
RID="*"
ID="*"Corresponding author. 相似文献
12.
Hazel F. O’Connor Jon M. Huibregtse 《Cellular and molecular life sciences : CMLS》2017,74(18):3363-3375
Protein ubiquitylation is an important post-translational modification, regulating aspects of virtually every biochemical pathway in eukaryotic cells. Hundreds of enzymes participate in the conjugation and deconjugation of ubiquitin, as well as the recognition, signaling functions, and degradation of ubiquitylated proteins. Regulation of ubiquitylation is most commonly at the level of recognition of substrates by E3 ubiquitin ligases. Characterization of the network of E3–substrate relationships is a major goal and challenge in the field, as this expected to yield fundamental biological insights and opportunities for drug development. There has been remarkable success in identifying substrates for some E3 ligases, in many instances using the standard protein–protein interaction techniques (e.g., two-hybrid screens and co-immunoprecipitations paired with mass spectrometry). However, some E3s have remained refractory to characterization, while others have simply not yet been studied due to the sheer number and diversity of E3s. This review will discuss the range of tools and techniques that can be used for substrate profiling of E3 ligases. 相似文献
13.
Corda D Hidalgo Carcedo C Bonazzi M Luini A Spanò S 《Cellular and molecular life sciences : CMLS》2002,59(11):1819-1832
Membrane fission is essential in various intracellular dissociative transport steps. The molecular mechanisms by which endocytic
vesicles detach from the plasma membrane are being rapidly elucidated. Much less is known about the fission mechanisms operating
at Golgi tubular networks; these include the Golgi transport and sorting stations, the trans-Golgi and cis-Golgi networks,
where the geometry and physical properties of the membranes differ from those at the cell surface. Here we discuss the lipid
and protein machineries that have so far been related to the fission process, with emphasis on those acting in the Golgi complex.
Received 10 May 2002; received after revision 20 June 2002; accepted 26 June 2002
RID="*"
ID="*"Corresponding author. 相似文献
14.
Yao Yao 《Cellular and molecular life sciences : CMLS》2017,74(6):1095-1115
Laminin, one of the most widely expressed extracellular matrix proteins, exerts many important functions in multiple organs/systems and at various developmental stages. Although its critical roles in embryonic development have been demonstrated, laminin’s functions at later stages remain largely unknown, mainly due to its intrinsic complexity and lack of research tools (most laminin mutants are embryonic lethal). With the advance of genetic and molecular techniques, many new laminin mutants have been generated recently. These new mutants usually have a longer lifespan and show previously unidentified phenotypes. Not only do these studies suggest novel functions of laminin, but also they provide invaluable animal models that allow investigation of laminin’s functions at late stages. Here, I first briefly introduce the nomenclature, structure, and biochemistry of laminin in general. Next, all the loss-of-function mutants/models for each laminin chain are discussed and their phenotypes compared. I hope to provide a comprehensive review on laminin functions and its loss-of-function models, which could serve as a reference for future research in this understudied field. 相似文献
15.
Wong RW 《Cellular and molecular life sciences : CMLS》2003,60(1):113-118
Generation of genetically engineered mice with either gain-of-function or loss-of-function mutations is the most popular
technique for determining gene functions and the interrelationship between molecules in vivo. These models have provided a
wealth of information about the developmental and physiological roles of oncogenes and growth factors. To date, transgenic
techniques have been used extensively to study the functions of the epidermal growth factor (EGF) family. This review highlights
some of the major recent findings pertinent to the EGF receptor (EGFR) and its ligands with special reference to elucidating
how EGF and its related growth factors work together to regulate reproduction, growth and development. Finally, future investigations
on ligand-ligand communications, EGFR and its ligands in neural stem cell research, and the mechanisms of EGFR signaling and
trafficking in cells are also suggested.
Received 24 May 2002; received after revision 15 July 2002; accepted 16 July 2002 相似文献
16.
17.
Myelin sheaths: glycoproteins involved in their formation,maintenance and degeneration 总被引:8,自引:0,他引:8
Quarles RH 《Cellular and molecular life sciences : CMLS》2002,59(11):1851-1871
Myelin sheaths are formed around axons by extending, biochemically modifying and spiraling plasma membranes of Schwann cells
in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS). Because glycoproteins are
prominent components of plasma membranes, it is not surprising that they have important roles in the formation, maintenance
and degeneration of myelin sheaths. The emphasis in this review is on four integral membrane glycoproteins. Two of them, protein
zero (P0) and peripheral myelin protein-22 (PMP-22), are components of compact PNS myelin. The other two are preferentially
localized in membranes of sheaths that are distinct from compact myelin. One is the myelin-associated glycoprotein, which
is localized at the inside of sheaths where it functions in glia-axon interactions in both the PNS and CNS. The other is the
myelin-oligodendrocyte glycoprotein, which is preferentially localized on the outside of CNS myelin sheaths and appears to
be an important target antigen in autoimmune demyelinating diseases such as multiple sclerosis.
Received 8 April 2002; received after revision 13 May 2002; accepted 22 May 2002 相似文献
18.
Homing endonucleases: structure, function and evolution 总被引:19,自引:0,他引:19
‘Homing’ is the lateral transfer of an intervening genetic sequence, either an intron or an intein, to a cognate allele that
lacks that element. The end result of homing is the duplication of the intervening sequence. The process is initiated by site-specific
endonucleases that are encoded by open reading frames within the mobile elements. Several features of these proteins make
them attractive subjects for structural and functional studies. First, these endonucleases, while unique, may be contrasted
with a variety of enzymes involved in nucleic acid strand breakage and rearrangement, particularly restriction endonucleases.
Second, because they are encoded within the intervening sequence, there are interesting limitations on the position and length
of their open reading frames, and therefore on their structures. Third, these enzymes display a unique strategy of flexible
recognition of very long DNA target sites. This strategy allows these sequences to minimize nonspecific cleavage within the
host genome, while maximizing the ability of the endonuclease to cleave closely related variants of the homing site. Recent
studies explain a great deal about the biochemical and genetic mechanisms of homing, and also about the structure and function
of several representative members of the homing endonuclease families.
Received 6 January 1999; received after revision 24 February 1999; accepted 24 February 1999 相似文献
19.
Biegel E Schmidt S González JM Müller V 《Cellular and molecular life sciences : CMLS》2011,68(4):613-634
Microbes have a fascinating repertoire of bioenergetic enzymes and a huge variety of electron transport chains to cope with
very different environmental conditions, such as different oxygen concentrations, different electron acceptors, pH and salinity.
However, all these electron transport chains cover the redox span from NADH + H+ as the most negative donor to oxygen/H2O as the most positive acceptor or increments thereof. The redox range more negative than −320 mV has been largely ignored.
Here, we have summarized the recent data that unraveled a novel ion-motive electron transport chain, the Rnf complex, that
energetically couples the cellular ferredoxin to the pyridine nucleotide pool. The energetics of the complex and its biochemistry,
as well as its evolution and cellular function in different microbes, is discussed. 相似文献
20.
Enzymes and receptors in the leukotriene cascade 总被引:7,自引:0,他引:7
Leukotrienes are a family of paracrine hormones derived from the oxidative metabolism of arachidonic acid. These lipid mediators
are recognized as important signal molecules in a variety of inflammatory and allergic conditions affecting the skin, joints,
gastrointestinal and respiratory systems, in particular asthma. Such conditions are typified by local pain, tissue edema,
hyperemia and functional losses. In the tissues, immunocompetent cells accumulate at the site of injury which contribute to
tissue damage and perpetuation of the disease process. Leukotrienes can elicit most, if not all, of these signs and symptoms.
Thus, leukotriene B4 is one of the most powerful chemotactic agents known to date and participates in the recruitment of leukocytes. The cysteinyl
leukotrienes, on the other hand, contract smooth muscles, particularly in the peripheral airways and microcirculation. Recently,
drugs which block the formation and action of leukotrienes have been introduced as novel antiasthmatic medications. This chapter
reviews the biochemistry, molecular biology and cell biology of the key enzymes and cognate receptors in the leukotriene cascade. 相似文献