Reassessing the Lineage Fusion Hypothesis for the Origin of Double Membrane Bacteria

A pathogen transmitted by the eriophyid mite, Aceria tulipae, infects a number of Gramineae producing symptoms similar to wheat spot mosaic virus (1). An electron microscope study of leaf ultrastructure from systemically infected Zea mays, Hordeum vulgare, and Triticum aestivum showed the presence of ovoid, double membrane bodies (0.1 - 0.2 microns) in the cytoplasm of parenchyma, phloem and epidermis cells (Fig. 1 ).

Download Full-text

The ultrastructure of the double membrane-bound bodies and endoplasmic reticulum in serial sections of wheat spot mosaic-affected wheat plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161023 ◽

1990 ◽

Vol 48 (3) ◽

pp. 694-695

Author(s):

M. H. Chen ◽

C. Hiruki

Keyword(s):

Endoplasmic Reticulum ◽

High Resolution ◽

Membrane Structure ◽

Mosaic Disease ◽

Serial Sections ◽

Thin Sections ◽

Double Membrane ◽

Southern Alberta ◽

Membrane Bound ◽

Scanning Em

Wheat spot mosaic disease was first discovered in southern Alberta, Canada, in 1956. A hitherto unidentified disease-causing agent, transmitted by the eriophyid mite, caused chlorosis, stunting and finally severe necrosis resulting in the death of the affected plants. Double membrane-bound bodies (DMBB), 0.1-0.2 μm in diameter were found to be associated with the disease.Young tissues of leaf and root from 4-wk-old infected wheat plants were fixed, dehydrated, and embedded in Spurr’s resin. Serial sections were collected on slot copper grids and stained. The thin sections were then examined with a Hitachi H-7000 TEM at 75 kV. The membrane structure of the DMBBs was studied by numbering them individually and tracing along the sections to see any physical connection with endoplasmic reticulum (ER) membranes. For high resolution scanning EM, a modification of Tanaka’s method was used. The specimens were examined with a Hitachi Model S-570 SEM in its high resolution mode at 20 kV.

Download Full-text

Portein-gold labelling of ultrathin sections of wheat spot mosaic-affected wheat plants

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160959 ◽

1990 ◽

Vol 48 (3) ◽

pp. 680-681

Author(s):

K. S. Zaychuk ◽

M. H. Chen ◽

C. Hiruki

Keyword(s):

Osmium Tetroxide ◽

Rnase A ◽

Leaf Ultrastructure ◽

Double Membrane ◽

Young Root ◽

Leaf Tissues ◽

Membrane Bound ◽

Ultrathin Sections ◽

Gold Labelling ◽

Electron Dense Core

Wheat spot mosaic (WSpM), which frequently occurs with wheat streak mosaic virus was first reported in 1956 from Alberta. Singly isolated, WSpM causes chlorotic spots, chlorosis, stunting, and sometimes death of the wheat plants. The vector responsible for transmission is the eriophyid mite, Eriophyes tulipae Kiefer. The examination of leaf ultrastructure by electron microscopy has revealed double membrane bound bodies (DMBB’s) 0.1-0.2 μm in diameter. Dispersed fibrils within these bodies suggested the presence of nucleic acid. However, neither ribosomes characteristic of bacteria, mycoplasma and the psittacosis group of organisms nor an electron dense core characteristic of many viruses was commonly evident.In an attempt to determine if the DMBB’s contain nucleic acids, RNase A, DNase I, and lactoferrin protein were conjugated with 10 nm colloidal gold as previously described. Young root and leaf tissues from WSpM-affected wheat plants were fixed in glutaraldehyde, postfixed in osmium tetroxide,and embedded in Spurr’s resin.

Download Full-text

Single- or double-membrane-bound vesicles and P, Ca, and Fe-containing granules in Xanthomonas citri cultured on a solid medium

Micron ◽

10.1016/j.micron.2021.103024 ◽

2021 ◽

Vol 143 ◽

pp. 103024

Author(s):

Junhyung Park ◽

A Reum Je ◽

Sang Gil Lee ◽

Jae Hyuck Jang ◽

Yang Hoon Huh ◽

...

Keyword(s):

Solid Medium ◽

Xanthomonas Citri ◽

Double Membrane ◽

Membrane Bound

Download Full-text

Mitochondrial Protein Network: From Biogenesis to Bioenergetics in Health and Disease

International Journal of Molecular Sciences ◽

10.3390/ijms22010001 ◽

2020 ◽

Vol 22 (1) ◽

pp. 1

Author(s):

Alessandra Ferramosca

Keyword(s):

Crucial Role ◽

Mitochondrial Protein ◽

Protein Network ◽

Eukaryotic Cells ◽

Double Membrane ◽

Health And Disease ◽

Membrane Bound

Mitochondria are double membrane-bound organelles which are essential for the viability of eukaryotic cells, because they play a crucial role in bioenergetics, metabolism and signaling [...]

Download Full-text

Simulation of S-Entropy Production during the Transport of Non-Electrolyte Solutions in the Double-Membrane System

Entropy ◽

10.3390/e22040463 ◽

2020 ◽

Vol 22 (4) ◽

pp. 463

Author(s):

Andrzej Ślęzak ◽

Wioletta M. Bajdur ◽

Kornelia M. Batko ◽

Radomir Šcurek

Keyword(s):

Entropy Production ◽

Transport Theory ◽

Membrane System ◽

Electrolyte Solutions ◽

Solute Flux ◽

Initial Moment ◽

Hydraulic Permeability ◽

Transport Parameters ◽

Double Membrane ◽

Solute Permeability

Using the classical Kedem–Katchalsky’ membrane transport theory, a mathematical model was developed and the original concentration volume flux (Jv), solute flux (Js) characteristics, and S-entropy production by Jv, ( ( ψ S ) J v ) and by Js ( ( ψ S ) J s ) in a double-membrane system were simulated. In this system, M1 and Mr membranes separated the l, m, and r compartments containing homogeneous solutions of one non-electrolytic substance. The compartment m consists of the infinitesimal layer of solution and its volume fulfills the condition Vm → 0. The volume of compartments l and r fulfills the condition Vl = Vr → ∞. At the initial moment, the concentrations of the solution in the cell satisfy the condition Cl < Cm < Cr. Based on this model, for fixed values of transport parameters of membranes (i.e., the reflection (σl, σr), hydraulic permeability (Lpl, Lpr), and solute permeability (ωl, ωr) coefficients), the original dependencies Cm = f(Cl − Cr), Jv = f(Cl − Cr), Js = f(Cl − Cr), ( Ψ S ) J v = f(Cl − Cr), ( Ψ S ) J s = f(Cl − Cr), Rv = f(Cl − Cr), and Rs = f(Cl − Cr) were calculated. Each of the obtained features was specially arranged as a pair of parabola, hyperbola, or other complex curves.

Download Full-text

ACUTE SENSORY DEAFNESS ORIGINATING FROM EXPERIMENTAL DOUBLE-MEMBRANE RUPTURE

Nippon Jibiinkoka Gakkai Kaiho ◽

10.3950/jibiinkoka.96.1065 ◽

1993 ◽

Vol 96 (7) ◽

pp. 1065-1072,1221 ◽

Cited By ~ 2

Author(s):

TAISUKE KOBAYASHI

Keyword(s):

Double Membrane ◽

Membrane Rupture

Download Full-text

Mechanism of protein import across the chloroplast envelope

Biochemical Society Transactions ◽

10.1042/bst0280485 ◽

2000 ◽

Vol 28 (4) ◽

pp. 485-491 ◽

Cited By ~ 9

Author(s):

K. Chen ◽

X. Chen ◽

D. J. Schnell

Keyword(s):

Protein Import ◽

Essential Elements ◽

Chloroplast Envelope ◽

Envelope Membrane ◽

Outer Envelope ◽

Double Membrane ◽

Protein Subunits ◽

Targeting Signals ◽

Outer Envelope Membrane ◽

Envelope Membranes

The development and maintenance of chloroplasts relies on the contribution of protein subunits from both plastid and nuclear genomes. Most chloroplast proteins are encoded by nuclear genes and are post-translationally imported into the organelle across the double membrane of the chloroplast envelope. Protein import into the chloroplast consists of two essential elements: the specific recognition of the targeting signals (transit sequences) of cytoplasmic preproteins by receptors at the outer envelope membrane and the subsequent translocation of preproteins simultaneously across the double membrane of the envelope. These processes are mediated via the co-ordinate action of protein translocon complexes in the outer (Toe apparatus) and inner (Tic apparatus) envelope membranes.

Download Full-text

Zoospore ultrastructure in the genus Rhizophydium (Chytridiales)

Canadian Journal of Botany ◽

10.1139/b78-290 ◽

1978 ◽

Vol 56 (19) ◽

pp. 2380-2404 ◽

Cited By ~ 25

Author(s):

D. J. S. Barr ◽

V. E. Hadland-Hartmann

Keyword(s):

Membrane System ◽

Double Membrane ◽

Lipid Globule ◽

Lateral Posterior ◽

Membrane Bound ◽

Relationship Of ◽

The Relationship ◽

Posterior Position ◽

Compact Cluster ◽

Peripheral Cytoplasm

The zoospore ultrastructure of 12 species of Rhizophydium is described. Species include the following: R. chlorogonii (Serbinow) Jaczewski; R. constantineani Saccardo; R. haynaldii (Schaarschmidt) Fischer; R. capillaceum Barr; two morphologically and cytologically different species, each previously identified as R. sphaerotheca Zopf; R. patellarium Scholz; R. biporosum (Couch) Barr; R. subangulosum (Braun) Rabenhorst; R. laterale (Braun) Rabenhorst; R. sphaerocarpum (Zopf) Fischer var. spirogyrae Barr; and two isolates of R. pollinis-pini (Braun) Zopf. The Rhizophydium zoospore is basically similar to the Chytridium zoospore having (1) the nucleus, a compact cluster of ribosomes, one or more mitochondria, and a microbody – lipid globule complex compartmentalized into the core of the zoospore by a double membrane system and (2) two to five microtubules connecting one side of the kinetosome to the rumposome on the lipid globule surface and thus anchoring the lipid globule in a lateral–posterior position in the zoospore. Rhizophydium patellarium does not have kinetosome-associated microtubules or a rumposome but does have the membrane-bound core area. In all species, a microbody and mitochondrion are associated with the lipid globule. The number of mitochondria varies from 1 in some species to several or to over 30 in other species. In one isolate of R. pollinis-pini, there is 1 large mitochondrion and in the other there were 30–35 small mitochondria. The peripheral cytoplasm of all species contains clusters of vesicles or endoplasmic reticulum which bud from the double membrane system, vesicles of moderate electron density, and vacuoles of various sizes; R. capillaceum, R. patellarium, and R. subangulosum have in addition vesicles which contain very electron-dense material. Rhizophydium capillaceum and R. sphaerocarpum zoospores have virus-like particles and the R. biporosum zoospore contains a paracrystalline body. The taxonomic significance of the observations and the relationship of Rhizophydium to other chytrids are stressed in the Discussion.

Download Full-text