Abstract：
:Lysozymes from family 22 of glycoside hydrolases are usually part of the defense system against bacteria. However in ruminant artiodactyls and saprophagous insects, lysozymes are involved in the digestion of bacteria. Here, we report the first crystallographic structure of a digestive lysozyme in its native and complexed forms, the structure of lysozyme 1 from Musca domestica larvae midgut (MdL1). Structural and biochemical data presented for MdL1 are analyzed in light of digestive lysozymes' traits. The structural core is similar, but a careful analysis of a structural alignment generated with other lysozymes c reveals that significant differences occur in coil regions. The loop from MdL1 defined by residues 98-100 has one deletion previous to residue Gln100, which leads to a less exposed conformation and might justify the resistance to proteolysis observed for MdL1. In addition, Gln100 is directly involved in a few hydrogen bonds to the ligand in a yet unobserved substrate binding mode. The pK(a)s of the MdL1 catalytic residues (Glu32 and Asp50) are lower (6.40 and 3.09, respectively) than those from Gallus gallus egg lysozyme (GgL, hen egg white lysozyme-HEWL) (6.61 and 3.85, respectively). A unique feature of MdL1 is a hydrogen bond between Thr107 Ogamma and Glu32 carboxylate group, which combined with the presence of Ser106 contributes to decrease the pK(a) of Glu32. Furthermore, in MdL1 the presence of Asn46 preventing the occurrence of an electrostatic repulsion with Asp50 and the increment in the solvent exposition of Asp50 due to Pro42 insertion contribute to reduce the pK(a) of Asp50. These structural elements affecting the pK(a)s of the catalytic residues should contribute to the acidic pH optimum presented by MdL1.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Cançado FC,Valério AA,Marana SR,Barbosa JAdoi
10.1016/j.jsb.2007.07.008subject
Has Abstractpub_date
2007-10-01 00:00:00pages
83-92issue
1eissn
1047-8477issn
1095-8657pii
S1047-8477(07)00154-2journal_volume
160pub_type
杂志文章abstract：:Macromolecular complexes perform their physiological functions by local rearrangements of their constituents and biochemically interacting with their reaction partners. These rearrangements may involve local rotations and the induction of local strains causing different mechanical efforts and stretches at the differen...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2016.04.001
更新日期：2016-07-01 00:00:00
abstract：:The ultrastructure of β-chitin microfibrils from a centric diatom, Thalassiosira, and a tubeworm, Lamellibrachia, was studied using electron diffraction and high-resolution electron microscopy. Electron microdiffraction diagrams corresponding to each projection of the β-chitin crystals were obtained, and all the data ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2011.07.001
更新日期：2011-10-01 00:00:00
abstract：:It has been known since the 19th century that coral skeletons are built of aragonite crystals with taxonomy-linked arrangements, but the way by which each coral species controls this crystallization process remains an unsolved question. The problem became still more intriguing when it was shown that isotopic compositi...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.03.004
更新日期：2005-06-01 00:00:00
abstract：:A new scanning probe microscope, the photonic force microscope (PFM), based on optical tweezers and two-photon absorption processes for biological applications is described. Optical tweezers are used to trap a fluorescent latex bead with a diameter of 200 nm in an aqueous solution in all three dimensions. The fluoresc...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3880
更新日期：1997-07-01 00:00:00
abstract：:Members of the Ku superfamily are DNA-end-binding proteins involved in non-homologous end-joining (NHEJ) DNA repair. The published crystal structure of human Ku-DNA complex reveals a heterodimer that forms a ring around dsDNA by means of the Ku core modules. These modules contain a highly conserved seven-stranded β-ba...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2010.05.011
更新日期：2010-12-01 00:00:00
abstract：:Structures of biological macromolecules determined by transmission cryoelectron microscopy (cryo-TEM) and three-dimensional image reconstruction are often displayed as surface-shaded representations with depth cueing along the viewed direction (Z cueing). Depth cueing to indicate distance from the center of virus part...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3902
更新日期：1997-10-01 00:00:00
abstract：:We have solved a crystal structure from Melanocarpus albomyces laccase expressed in the filamentous fungus Trichoderma reesei (rMaL) at 1.3A resolution by using synchrotron radiation at 100K. At the moment, this is the highest resolution that has been attained for any multicopper oxidase. The present structure confirm...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2007.12.003
更新日期：2008-04-01 00:00:00
abstract：:BCP1 is a protein enriched in the nucleus that is required for Mss4 nuclear export and identified as the chaperone of ribosomal protein Rpl23 in Saccharomyces cerevisiae. According to sequence homology, BCP1 is related to the mammalian BRCA2-interacting protein BCCIP and belongs to the BCIP protein family (PF13862) in...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2020.107605
更新日期：2020-10-01 00:00:00
abstract：:Mononuclear macrophages are important immune cells in the organisms. The complicated membrane structure underlying the diverse functions of mononuclear-macrophage has been largely unresolved. As a representative of monocyte-derived macrophages, the membrane structure of PMA differentiated THP-1 cells was comprehensive...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.04.002
更新日期：2019-06-01 00:00:00
abstract：:Microfluidics, or lab-on-a-chip technology, is proving to be a powerful, rapid, and efficient approach to a wide variety of bioanalytical and microscale biopreparative needs. The low materials consumption, combined with the potential for packing a large number of experiments in a few cubic centimeters, makes it an att...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/s1047-8477(03)00049-2
更新日期：2003-04-01 00:00:00
abstract：:Two-dimensional crystallization on lipid monolayers is a versatile tool to obtain structural information of proteins by electron microscopy. An inherent problem with this approach is to prepare samples in a way that preserves the crystalline order of the protein array and produces specimens that are sufficiently flat ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2007.06.002
更新日期：2007-12-01 00:00:00
abstract：:Poly(A)-binding protein (PABP) is an RNA-binding protein that binds specifically to the poly(A) tail of messenger RNAs in eukaryotes. The PABP/poly(A) tail complex has been implicated as being important in promoting the efficient initiation of translation as well as in maintaining the integrity of the mRNA. PABP binds...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3864
更新日期：1997-07-01 00:00:00
abstract：:The repetitive Gly-X-Y sequence is the telltale sign of triple helical domains in collagens and collagen-like proteins. Most collagen sequences contain sporadic interruptions of this pattern, which may have functional roles in molecular flexibility, assembly or molecular recognition. However, the structural signatures...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2014.03.022
更新日期：2014-06-01 00:00:00
abstract：:Staphylococcus aureus hibernation promoting factor (SaHPF) is responsible for the formation of 100S ribosome dimers, which in turn help this pathogen to reduce energy spent under unfavorable conditions. Ribosome dimer formation strongly depends on the dimerization of the C-terminal domain of SaHPF (CTDSaHPF). In this ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.107408
更新日期：2020-01-01 00:00:00
abstract：:The structure and motility of the Mollicutes (Spiroplasma, Mycoplasma, and Acholeplasma) are briefly reviewed. The data are presented from the perspective of prokaryotic and eukaryotic motors, cytoskeletons, and cell motility. The Mollicutes are eubacteria derived from Clostridia by regressive evolution and genome red...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.1998.4063
更新日期：1998-12-15 00:00:00
abstract：:We report a detailed work of composition and location of naturally formed iron biominerals in plant cells tissues grown in iron rich environments as Imperata cylindrica. This perennial grass grows on the Tinto River banks (Iberian Pyritic Belt) in an extreme acidic ecosystem (pH∼2.3) with high concentration of dissolv...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2015.11.005
更新日期：2016-01-01 00:00:00
abstract：:Cryoelectron microscopy makes it possible to record high-resolution detail from large and complex structures. However, its application to understanding cellular structure is limited by the requirement that samples should be no thicker than approximately 0.5-1 microm. Therefore it is important to develop the ability to...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/s1047-8477(03)00016-9
更新日期：2003-05-01 00:00:00
abstract：:The genomic DNA in cells of Escherichia coli is localized in one or two compact, phase-like regions with characteristic shapes. Nucleoids undergo progressive changes in shape and compaction in the presence of drugs such as chloramphenicol or puromycin. Forces which influence nucleoid shape and compaction are reviewed,...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/j.jsb.2006.03.022
更新日期：2006-11-01 00:00:00
abstract：:A simple, fast and efficient noise-reduction protocol for three-dimensional electron tomographic reconstructions of biological material is presented. The approach is based on iterative application of median filtering and shows promise for automatic noise reduction as a pre-processor for automated data analysis tools w...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2006.10.030
更新日期：2007-05-01 00:00:00
abstract：:By taking advantage of network-based computing and the recent developments in Web interfaces, centralized research facilities housing specialized and unique imaging instruments along with associated high-performance computing can be made available to researchers for use from their own laboratories. In addition to incr...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.1999.4095
更新日期：1999-04-01 00:00:00
abstract：:Sickle hemoglobin (HbS) polymerization initiates in the deoxy state with the binding of hydrophobic patch formed by the isopropyl group of βVal6 residue of a hemoglobin tetramer with the hydrophobic pocket of another tetramer, whose hydrophobic patch binds to the hydrophobic groove of a third molecule. Subsequent elon...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.04.009
更新日期：2017-07-01 00:00:00
abstract：:Upon illumination the visual receptor rhodopsin (Rho) transitions to the activated form Rho(∗), which binds the heterotrimeric G protein, transducin (Gt) causing GDP to GTP exchange and Gt dissociation. Using succinylated concanavalin A (sConA) as a probe, we visualized native Rho dimers solubilized in 1mM n-dodecyl-β...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2013.02.014
更新日期：2013-05-01 00:00:00
abstract：:Trypsin treatment of staphylococcal alpha-toxin cleaves the molecule into two roughly equally sized parts, which results in inactivation of the toxin. Tetragonal arrays of oligomers, closely resembling the native ones, can however be formed on lipid layers. From tilted views of negatively stained crystals a 3D structu...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/1047-8477(92)90024-5
更新日期：1992-05-01 00:00:00
abstract：:Sequence comparisons have been undertaken for all hair and epithelial keratin IF chains from a single species--human. The results lead to several new proposals. First, it is clear that not only is the chain structure of the molecule an obligate heterodimer but promiscuous association of Type I and Type II chains must ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2006.12.002
更新日期：2007-06-01 00:00:00
abstract：:We consider the problem of estimating an unbiased and reference-free ab initio model for non-symmetric molecules from images generated by single-particle cryo-electron microscopy. The proposed algorithm finds the globally optimal assignment of orientations that simultaneously respects all common lines between all imag...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.09.007
更新日期：2017-11-01 00:00:00
abstract：:The ultrastructure of familial amyloid polyneuropathy (FAP) amyloid fibrils was examined with high-resolution electron microscopy and immunolabeling. Sural nerve biopsies from FAP (Met 30) patients as well as control tissues were prepared for thin-section observations. Extracellular spaces in the vicinity of myelinate...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.4052
更新日期：1998-12-01 00:00:00
abstract：:The first step to understanding brain function is to determine the brain's network structure. We report a three-dimensional analysis of the brain network of the fruit fly Drosophila melanogaster by synchrotron-radiation tomographic microscopy. A skeletonized wire model of the left half of the brain network was built b...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2013.08.012
更新日期：2013-11-01 00:00:00
abstract：:In Streptomycetes, tetracycline repressor family of transcription regulators (TetR-FTRs) controls various biological processes including antibiotic biosynthesis, cellular morphology and innate resistance. Here, we focus on understanding the structural basis of transcription regulation by CprB, a member of TetR-FTRs fr...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2017.03.006
更新日期：2017-05-01 00:00:00
abstract：:Native troponin-tropomyosin complex was isolated from Lethocerus indicus indirect flight muscle and tested for function. It was shown by rotary shadowing and by forming paracrystals on monolayers that the regulatory complex consists of a troponin head region approximately 130 A in diameter and a 400-A-long troponin T-...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1996.3834
更新日期：1997-02-01 00:00:00
abstract：:Non-collagenous proteins such as osteocalcin function as regulators of the mineralization process in bone. Osteocalcin undergoes post-translational modification adding an extra carboxylate group on three of its glutamate residues to enhance interaction with bone mineral. In this work, we examine regulation of biomimet...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2019.04.014
更新日期：2019-08-01 00:00:00
