scholarly journals THE THREE-DIMENSIONAL STRUCTURE OF THE BASAL BODY FROM THE RHESUS MONKEY OVIDUCT

1972 ◽  
Vol 54 (2) ◽  
pp. 246-265 ◽  
Author(s):  
Richard G. W. Anderson
Keyword(s):  
Basal Body ◽  
Three Dimensional ◽  
Longitudinal Axis ◽  
Scale Model ◽  
Dimensional Structure ◽  
Transverse Axis ◽  
Longitudinal Edge ◽  
Striated Rootlet ◽  
Basal Foot ◽  
Base View

The structure of the oviduct basal body has been reconstructed from serial, oblique, and tangential sections This composite information has been used to construct a three-dimensional scale model of the organelle The walls are composed of nine equally spaced sets of three tubules, which run from base to apex pitched to the left at a 10°–15° angle to the longitudinal axis. The transverse axis of each triplet set at its basal end intersects a tangent to the lumenal circumference of the basal body at a 40° angle (triplet angle). As the triplet set transverses from base to apex, it twists toward the lumen on the longitudinal axis of the inner A tubule; therefore, the triplet angle is 10° at the basal body-cilium junction. Strands of fibrous material extend from the basal end of each triplet to form a striated rootlet. A pyramidal basal foot projects at right angles from the midregion of the basal body. In the apex, a 175 mµ long trapezoidal sheet is attached to each triplet set. The smaller of the two parallel sides is attached to all three tubules while the longitudinal edge (one of the equidistant anti-parallel sides) is attached to the C tubule. The sheet faces counterclockwise (apex to base view) and gradually unfolds from base to apex; the outside corner merges with the cell membrane.

The three-dimensional structure of frozen-hydrated left- and right-handed forms of bacterial flagellar filaments from an identical serotype

1986 ◽  
Vol 44 ◽  
pp. 298-299
Author(s):  
S. Trachtenberg ◽  
D. J. DeRosier
Keyword(s):  
Ionic Strength ◽  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Protein Species ◽  
Liquid Environment ◽  
Bacterial Flagellum ◽  
Left And Right ◽  
Rotary Motor ◽  
Helical Parameters

The bacterial cell is propelled through the liquid environment by means of one or more rotating flagella. The bacterial flagellum is composed of a basal body (rotary motor), hook (universal coupler), and filament (propellor). The filament is a rigid helical assembly of only one protein species — flagellin. The filament can adopt different morphologies and change, reversibly, its helical parameters (pitch and hand) as a function of mechanical stress and chemical changes (pH, ionic strength) in the environment.

Ultrastructure of the basal body apparatus in epidermal cells of a sponge larva (Aplysilla SP: Demospongiae)

1992 ◽  
Vol 50 (1) ◽  
pp. 928-929
Author(s):  
R.L. Pinto ◽  
R.M. Woollacott
Keyword(s):  
Sodium Bicarbonate ◽  
Epoxy Resin ◽  
Basal Body ◽  
Phosphate Buffer ◽  
Similar Data ◽  
Basal Apparatus ◽  
Striated Rootlet ◽  
The Common ◽  
Basal Foot ◽  
Sexually Mature

The basal body and its associated rootlet are the organelles responsible for anchoring the flagellum or cilium in the cytoplasm. Structurally, the common denominators of the basal apparatus are the basal body, a basal foot from which microtubules or microfilaments emanate, and a striated rootlet. A study of the basal apparatus from cells of the epidermis of a sponge larva was initiated to provide a comparison with similar data on adult sponges.Sexually mature colonies of Aplysillasp were collected from Keehi Lagoon Marina, Honolulu, Hawaii. Larvae were fixed in 2.5% glutaraldehyde and 0.14 M NaCl in 0.2 M Millonig’s phosphate buffer (pH 7.4). Specimens were postfixed in 1% OsO4 in 1.25% sodium bicarbonate (pH 7.2) and embedded in epoxy resin. The larva ofAplysilla sp was previously described (as Dendrilla cactus) based on live observations and SEM by Woollacott and Hadfield.

An Overview on 3D Site Modelling in Civil Engineering

2020 ◽  
pp. 108-127
Author(s):  
Muthuminal R.
Keyword(s):  
Computer Aided Design ◽  
Civil Engineering ◽  
Three Dimensional ◽  
3D Modelling ◽  
Scale Model ◽  
Dimensional Structure ◽  
Scale Modelling ◽  
Basic Concepts ◽  
A Site ◽  
Aided Design

In past decades, for developing a site, engineers used the process of creating a scale model in order to determine their behaviour and to sketch the details collected manually using the drafting process, which behaves as a referring material during the construction of structures. Due to the boom in technology and limitations in drafting, the drawings have been digitized using computer-aided design (CAD) software as a two-dimensional structure (2D). Currently, these drawings are detailed as a three-dimensional structure (3D) that is briefly noted as 3D modelling. Three-dimensional site modelling is an active area that is involved in research and development of models in several fields that has been originated from the scale modelling. In this chapter, the topic 3D site modelling in civil engineering is discussed. First of all, the basic concepts of scale modelling, architectural modelling, and structural modelling are discussed. Then the concept of virtual-based 3D site modelling, its importance, benefits, and steps involved in site modelling are briefed.

Cryo-Electron Microscopy of Spiroplasma Virus SpV4

1997 ◽  
Vol 3 (S2) ◽  
pp. 87-88
Author(s):  
P.R. Chipman ◽  
R. Mckenna ◽  
J. Renaudin ◽  
T.S. Baker
Keyword(s):  
Electron Microscopy ◽  
Cross Section ◽  
Outer Surface ◽  
Average Distance ◽  
Three Dimensional ◽  
Longitudinal Axis ◽  
Lytic Cycle ◽  
Dimensional Structure ◽  
Circular Dna ◽  
Cryo Electron Microscopy

Spiroplasma, a wall-free prokaryote of the class Mollicutes, is host to a small, naked, single-stranded DNA, isometric virus. Spiroplasma virus SpV4 belongs to the Microviridae family, members of which are non-enveloped, have icosahedral capsids, release progeny through a lytic cycle, and contain circular DNA.Measurements obtained from negatively stained SpV4 particles revealed a nucleocapsid of 27nm in diameter (figure 1). The three-dimensional structure reported here, obtained from unstained particles suspended in a layer of vitreous ice (figure 2), is in agreement with these earlier results, suggesting a 27nm average distance through the nucleocapsid (figure 3). Unreported in earlier studies is the presence of a 6nm, mushroom-shaped protrusion (made up of a stalk, 2.3nm long and 1.3nm wide, and a globular bud of dimensions ≈4.0×4.0×3.7nm) stemming from an ≈1.5nm deep depression at each of the 3-fold icosahedral axes of the virion. A cross section through the longitudinal axis of one protuberance (figure 4) reveals a cylindrical dimple (≈1.0nm in diameter and 2.3nm deep), originating on the axis of the outer surface of the globular bud domain.

The Structure and Subunit Organization of the Bacterial Flagellar Motor by Scanning Transmission Electron Microscopy and Cryoelectron Microscopy

1990 ◽  
Vol 48 (1) ◽  
pp. 278-279
Author(s):  
Gina E. Sosinsky ◽  
Noreen R. Francis ◽  
Charles D. DeRosier ◽  
David J. DeRosier ◽  
James Hainfeld ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Cryoelectron Microscopy ◽  
Data Set ◽  
Bacterial Flagellum ◽  
The Individual ◽  
The Masses ◽  
Subunit Organization

The bacterial flagellum is unique in having a rotary motor. In Salmonella typhimurium, the basal body, a component of the motor, consists of four rings (denoted M, S, L, and P) threaded on a coaxial rod. The M, L, and P rings are each composed of a different protein: FliF=61 kD, FlgH=22 kD, and FlgI=36 kD, respectively. The rod contains at least four different proteins: FlgB=15 kD, FlgC=14 kD, FlgF=26 kD, and FlgG=28 kD. Using quantitative gel analysis, Jones et al. estimated that there are about 26 copies of FlgG, FlgH, Flgl and FliF, and 6 copies of FlgB, FlgC and FlgF per basal body. The total mass of these 7 proteins per basal body is ∽4200 kD. There appear to be additional proteins in the basal body, but their locations and amounts are not known. Our aim is to produce subcomplexes of the basal body and determine their structures and masses using electron microscopy. This approach is complementary to that of Jones et al. and can reveal the presence and amounts of as yet unidentified components. We find, in pH3- or pH4-treated preparations of basal bodies, four subcomplexes of the hook basal body complex (HBB): the HLPRS (hook, L and P rings on the distal rod, proximal rod, S ring); the HLPR (lacks the M and S rings), the HLP (lacks the M, S, and proximal rod); and the LP complex (Figs. 1 and 2). We have been able to visualize the three-dimensional structure and the subunit organization using the combined techniques of cryoelectron microscopy and image analysis. These studies suggest that the S ring is a separate component from the rod or M ring and that the rod consists of two sections. Because the different sub-complexes are distinguishable in a field of particles, we measured the molecular masses of the individual subcomplexes using the Brookhaven STEM even though these preparations are not homogeneous (Fig. 3). All the structures analyzed so far had hooks attached. We measured the length and mass/length from STEM images and then subtracted the mass of the hook. Preliminary results show that the molecular mass of the hookless basal body is 4400−500 kD (n=165), that of the LP-rod (proximal and distal) is 3500±300 kD (n=52), and that of the LP-distal rod is 2300±450 kD (n=76) (Fig. 4). The difference between these three molecular weights gives estimates of the mass of the M and S rings (4400 - 3500 = 900 kD) and proximal rod, 3500 − 2300 = 1200 kD. The mass of the M and S rings may be underestimated due to the undetected presence of HLPRS subcomplexes in the basal body data set. We are presently measuring and re-evaluating masses for the subcomplexes in order to get more accurate estimates of the masses and numbers of subunits.

scholarly journals Three-dimensional structure of basal body triplet revealed by electron cryo-tomography

2011 ◽  
Vol 31 (3) ◽  
pp. 552-562 ◽  
Author(s):  
Sam Li ◽  
Jose-Jesus Fernandez ◽  
Wallace F Marshall ◽  
David A Agard
Keyword(s):  
Basal Body ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Three Dimensional Structure

Conformation of Ribosomes from Escherichia Coli

1974 ◽  
Vol 32 ◽  
pp. 210-211
Author(s):  
M. Boublik ◽  
W. Hellmann ◽  
F. Jenkins
Keyword(s):  
Binding Sites ◽  
Ribosomal Proteins ◽  
Fluorescent Dyes ◽  
Protein Biosynthesis ◽  
Three Dimensional ◽  
Spatial Arrangement ◽  
Dimensional Structure ◽  
Complete Understanding ◽  
And Function

The present knowledge of the three-dimensional structure of ribosomes is far too limited to enable a complete understanding of the various roles which ribosomes play in protein biosynthesis. The spatial arrangement of proteins and ribonuclec acids in ribosomes can be analysed in many ways. Determination of binding sites for individual proteins on ribonuclec acid and locations of the mutual positions of proteins on the ribosome using labeling with fluorescent dyes, cross-linking reagents, neutron-diffraction or antibodies against ribosomal proteins seem to be most successful approaches. Structure and function of ribosomes can be correlated be depleting the complete ribosomes of some proteins to the functionally inactive core and by subsequent partial reconstitution in order to regain active ribosomal particles.

Three-Dimensional Reconstruction Using Stereo Pairs from Serial Thick Sections

1977 ◽  
Vol 35 ◽  
pp. 562-563
Author(s):  
Robert Glaeser ◽  
Thomas Bauer ◽  
David Grano
Keyword(s):  
Three Dimensional ◽  
Dimensional Structure ◽  
Serial Sections ◽  
Thin Sections ◽  
3 Dimensional ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Dimensional Reconstruction ◽  
Stereo Imagery ◽  
Whole Mounts

In transmission electron microscopy, the 3-dimensional structure of an object is usually obtained in one of two ways. For objects which can be included in one specimen, as for example with elements included in freeze- dried whole mounts and examined with a high voltage microscope, stereo pairs can be obtained which exhibit the 3-D structure of the element. For objects which can not be included in one specimen, the 3-D shape is obtained by reconstruction from serial sections. However, without stereo imagery, only detail which remains constant within the thickness of the section can be used in the reconstruction; consequently, the choice is between a low resolution reconstruction using a few thick sections and a better resolution reconstruction using many thin sections, generally a tedious chore. This paper describes an approach to 3-D reconstruction which uses stereo images of serial thick sections to reconstruct an object including detail which changes within the depth of an individual thick section.

Electron Microscopy of Cytoplasmic Contractile Proteins

1978 ◽  
Vol 36 (3) ◽  
pp. 606-614 ◽  
Author(s):  
T.D. Pollard ◽  
P. Maupin
Keyword(s):  
Electron Microscopy ◽  
Actin Filaments ◽  
Three Dimensional ◽  
Uranyl Acetate ◽  
Contractile Proteins ◽  
Dimensional Structure ◽  
X Ray Diffraction ◽  
Cytoplasmic Matrix ◽  
Computer Image Processing ◽  
Nonmuscle Cells

In this paper we review some of the contributions that electron microscopy has made to the analysis of actin and myosin from nonmuscle cells. We place particular emphasis upon the limitations of the ultrastructural techniques used to study these cytoplasmic contractile proteins, because it is not widely recognized how difficult it is to preserve these elements of the cytoplasmic matrix for electron microscopy. The structure of actin filaments is well preserved for electron microscope observation by negative staining with uranyl acetate (Figure 1). In fact, to a resolution of about 3nm the three-dimensional structure of actin filaments determined by computer image processing of electron micrographs of negatively stained specimens (Moore et al., 1970) is indistinguishable from the structure revealed by X-ray diffraction of living muscle.

A New 1000kv Electron Microscope

1969 ◽  
Vol 27 ◽  
pp. 100-101
Author(s):  
J.L. Williams ◽  
K. Heathcote ◽  
E.J. Greer
Keyword(s):  
Electron Microscope ◽  
Direct Observation ◽  
High Voltage ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Specimen Thickness ◽  
Voltage Electron ◽  
High Voltage Electron Microscope ◽  
Dynamic Experiments ◽  
Conventional Instrument

High Voltage Electron Microscope already offers exciting experimental possibilities to Biologists and Materials Scientists because the increased specimen thickness allows direct observation of three dimensional structure and dynamic experiments on effectively bulk specimens. This microscope is designed to give maximum accessibility and space in the specimen region for the special stages which are required. At the same time it provides an ease of operation similar to a conventional instrument.

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