Hyphal tip growth in Achlya. II. Subcellular localization of cellulase and associated enzymes

1980 ◽  
Vol 26 (9) ◽  
pp. 1141-1146 ◽  
Author(s):  
T. W. Hill ◽  
J. T. Mullins
Keyword(s):  
Electron Microscopy ◽  
Tip Growth ◽  
Cellulase Activity ◽  
Single Type ◽  
Similar Distribution ◽  
Cytochemical Localization ◽  
Isolation And Characterization ◽  
Cytoplasmic Vesicles ◽  
Hyphal Tip

The isolation and characterization of cellulase-containing membranes of Achlya ainbisexnalis Raper was attempted by differential and density gradient centrifugations. Maximum cellulase activity was found at an isopycnic density of 1.19 g/cm3, although some activity was found at other densities. A similar distribution of activity was shown by IDPase, ATPase, UDPG transferase, and by sedimentable carbohydrate. The coequilibration and steady enrichment of these activities during purification suggests their presence in a single type of subcellular particle. It was not possible to identify clearly the particle(s) in question from isolated fractions by electron microscopy, but when compared with the cytochemical localization of carbohydrate and IDPase in intact hypha, cytoplasmic vesicles with 150-mm diameters seem to be likely candidates.

Hyphal tip growth in Achlya. I. Cytoplasmic organization

1980 ◽  
Vol 26 (9) ◽  
pp. 1132-1140 ◽  
Author(s):  
T. W. Hill ◽  
J. T. Mullins
Keyword(s):  
Electron Microscopy ◽  
Fibrous Material ◽  
Tip Growth ◽  
Phosphotungstic Acid ◽  
Chromic Acid ◽  
Periodic Acid ◽  
Cytoplasmic Vesicles ◽  
Cytoplasmic Organization ◽  
Apical Vesicles ◽  
Hyphal Tip

Growing apices of Achlya ambisexttalis Raper hyphae were examined by electron microscopy using cytochemical techniques. Apical vesicles can be grouped into two major classes based upon size and cytochemical reactions. Vesicles of the most prominent class are about 150 nm in diameter and possess contents which appear fibrous in thin section. This fibrous material reacts positively with the periodic acid – silver methenamine (PASM) cytochemical test for polysaccharides. Most of these same vesicles also display IDPase activity, and a smaller number display acid phosphatase activity. Vesicles of the second class are about 80 nm in diameter, and include coated vesicles and others which react positively for IDPase activity. They show a negative PASM reaction in contrast with the larger vesicles. Some of these smaller vesicles are stained by the phosphotungstic acid – chromic acid (PTA–CrO3) stain, whereas 150-nm vesicles are not. The source of at least some vesicles of both major classes appears to be the Golgi apparatus. It is proposed that the IDPase activity and carbohydrate content of the 150-nm cytoplasmic vesicles could serve as useful markers in their isolation.

scholarly journals Isolation and Characterization of Cellulose Nanofibers fromGigantochloa scortechiniias a Reinforcement Material

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Chaturbhuj K. Saurabh ◽  
Asniza Mustapha ◽  
M. Mohd. Masri ◽  
A. F. Owolabi ◽  
M. I. Syakir ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cellulose Nanofibers ◽  
X Ray Diffraction ◽  
X Ray ◽  
Isolation And Characterization ◽  
Transmission Electron ◽  
Reinforcement Material ◽  
Bamboo Fibers ◽  
Ft Ir

Cellulose nanofibers (CNF) were isolated fromGigantochloa scortechiniibamboo fibers using sulphuric acid hydrolysis. This method was compared with pulping and bleaching process for bamboo fiber. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and thermogravimetric analysis were used to determine the properties of CNF. Structural analysis by FT-IR showed that lignin and hemicelluloses were effectively removed from pulp, bleached fibers, and CNF. It was found that CNF exhibited uniform and smooth morphological structures, with fiber diameter ranges from 5 to 10 nm. The percentage of crystallinity was significantly increased from raw fibers to cellulose nanofibers, microfibrillated, along with significant improvement in thermal stability. Further, obtained CNF were used as reinforcement material in epoxy based nanocomposites where tensile strength, flexural strength, and modulus of nanocomposites improved with the addition of CNF loading concentration ranges from 0 to 0.7%.

Isolation and characterization of the peptidoglycans from selected Gram-positive and Gram-negative periodontal pathogens

1985 ◽  
Vol 31 (2) ◽  
pp. 154-160 ◽  
Author(s):  
M. R. Barnard ◽  
S. C. Holt
Keyword(s):  
Electron Microscopy ◽  
Diaminopimelic Acid ◽  
Muramic Acid ◽  
Periodontal Pathogens ◽  
Gram Positive ◽  
Gram Negative ◽  
Isolation And Characterization ◽  
Bacteroides Gingivalis ◽  
Scanning Electron

The peptidoglycans from several Gram-negative and Gram-positive periodontal pathogens were isolated, purified, and characterized both morphologically and chemically. In addition, the effects of the mureolytic enzymes, lysozyme, M-1 N-acetyl-muramidase, and the AM-3 endopeptidase, on the peptidoglycans were examined. These enzymes were found to be highly effective in the degradation of the purified peptidoglycans; however, a Bacteroides capillus peptidoglycan–protein complex exhibited a greater resistance to these enzymes. Morphologically, the peptidoglycans consisted of large saccular sheets which, when viewed by scanning electron microscopy, contained numerous holes and tears. Chemically, the peptidoglycans consisted of muramic acid, glucosamine, alanine, glutamic acid, and meso-diaminopimelic acid (DAP). One Bacteroides species, Bacteroides gingivalis strain W, contained glycine and LL-DAP, suggestive of an indirectly cross-linked A3γ peptidoglycan.

scholarly journals Isolation and Characterization of a New Subtype of Borna Disease Virus

2000 ◽  
Vol 74 (12) ◽  
pp. 5655-5658 ◽  
Author(s):  
Norbert Nowotny ◽  
Jolanta Kolodziejek ◽  
Christian O. Jehle ◽  
Angelika Suchy ◽  
Peter Staeheli ◽  
...  
Keyword(s):  
Disease Virus ◽  
Single Type ◽  
The Novel ◽  
Borna Disease Virus ◽  
Diagnostic Assays ◽  
Isolation And Characterization ◽  
First Time ◽  
Reference Strains ◽  
Borna Disease

ABSTRACT Borna disease virus (BDV), the causative agent of severe meningoencephalitis in a wide variety of animal species, has been considered to be genetically invariable and to form a single type within the genus Bornavirus of the familyBornaviridae. BDV infections are of particular interest, because for the first time a virus infection appears to be linked to human psychiatric disorders. We now describe a new subtype of BDV isolated from a horse which was euthanatized due to severe, incurable neurological disease. The nucleotide sequence of this new strain, named No/98, differs from the reference strains by more than 15%, and the subtype is difficult to detect by standard reverse transcriptase PCR protocols. The nucleotide exchanges of the novel BDV isolate have surprisingly little effect on the primary structures of most viral proteins, with the notable exception of the X protein (p10), which is only 81% identical to its counterpart in reference strains. Our data indicate that the genome of BDV is far more variable than previously assumed and that naturally occurring subtypes may escape detection by currently used diagnostic assays.

scholarly journals Genome sequence and characterization of five bacteriophages infecting Streptomyces coelicolor and Streptomyces venezuelae: Alderaan, Coruscant, Dagobah, Endor1 and Endor2

2020 ◽  
Author(s):  
Aël Hardy ◽  
Vikas Sharma ◽  
Larissa Kever ◽  
Julia Frunzke
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Streptomyces Coelicolor ◽  
Morphological Differentiation ◽  
Viral Diversity ◽  
Isolation And Characterization ◽  
Phage Evolution ◽  
Transmission Electron ◽  
Family Based

AbstractStreptomyces are well-known antibiotic producers, and are also characterized by a complex morphological differentiation. Streptomyces, like all bacteria, are confronted with the constant threat of phage predation, which in turn shapes bacterial evolution. However, despite significant sequencing efforts recently, relatively few phages infecting Streptomyces have been characterized compared to other genera. Here, we present the isolation and characterization of five novel Streptomyces phages. All five phages belong to the Siphoviridae family, based on their morphology as determined by transmission electron microscopy. Genome sequencing revealed that four of them were temperate phages, while one had a lytic lifestyle. Moreover, one of the newly sequenced phages shows very little homology to already described phages, highlighting the still largely untapped viral diversity. Altogether, this study expands the number of characterized phages of Streptomyces and sheds light on phage evolution and phage-host dynamics in Streptomyces.

scholarly journals Isolation and characterization of kinetoplast DNA from bloodstream form of Trypanosoma brucei.

1978 ◽  
Vol 76 (2) ◽  
pp. 293-309 ◽  
Author(s):  
A H Fairlamb ◽  
P O Weislogel ◽  
J H Hoeijmakers ◽  
P Borst
Keyword(s):  
Electron Microscopy ◽  
Trypanosoma Brucei ◽  
Contour Length ◽  
Kinetoplast Dna ◽  
East African ◽  
S1 Nuclease ◽  
Isolation And Characterization ◽  
Trypanosoma Equiperdum ◽  
Double Networks

We have used restriction endonucleases PstI, EcoRI, HapII, HhaI, and S1 nuclease to demonstrate the presence of a large complex component, the maxi-circle, in addition to the major mini-circle component in kinetoplast DNA (kDNA) networks of Trypanosoma brucei (East African Trypanosomiasis Research Organization [EATRO] 427). Endonuclease PstI and S1 nuclease cut the maxi-circle at a single site, allowing its isolation in a linear form with a mol wt of 12.2 x 10(6), determined by electron microscopy. The other enzymes give multiple maxi-circle fragments, whose added mol wt is 12-13 x 10(6), determined by gel electrophoresis. The maxi-circle in another T. brucei isolate (EATRO 1125) yields similar fragments but appears to contain a deletion of about 0.7 x 10(6) daltons. Electron microscopy of kDNA shows the presence of DNA considerably longer than the mini-circle contour length (0.3 micron) either in the network or as loops extending from the edge. This long DNA never exceeds the maxi-circle length (6.3 microns) and is completely removed by digestion with endonuclease PstI. 5-10% of the networks are doublets with up to 40 loops of DNA clustered between the two halves of the mini-circle network and probably represent a division stage of the kDNA. Digestion with PstI selectively removes these loops without markedly altering the mini-circle network. We conclude that the long DNA in both single and double networks represents maxi-circles and that long tandemly repeated oligomers of mini-circles are (virtually) absent. kDNA from Trypanosoma equiperdum, a trypanosome species incapable of synthesizing a fully functional mitochondrion, contains single and double networks of dimensions similar to those from T. brucei but without any DNA longer than mini-circle contour length. We conclude that the maxi-circle of trypanosomes is the genetic equivalent of the mitochondrial DNA (mtDNA) of other organisms.

scholarly journals Surface ultrastructure and elasticity in growing tips and mature regions of Aspergillus hyphae describe wall maturation

Microbiology ◽  
2005 ◽  
Vol 151 (11) ◽  
pp. 3679-3688 ◽  
Author(s):  
Hui Ma ◽  
Laelie A. Snook ◽  
Susan G. W. Kaminskyj ◽  
Tanya E. S. Dahms
Keyword(s):  
Electron Microscopy ◽  
Tip Growth ◽  
Living Cells ◽  
Surface Ultrastructure ◽  
Force Microscopy ◽  
Atomic Force ◽  
Young Branch ◽  
Hyphal Tip ◽  
Cryo Scanning Electron Microscopy ◽  
Scanning Electron

This study reports the first direct, high-resolution physical and structural evidence of wall changes during hyphal tip growth, visualized by atomic force microscopy (AFM) in Aspergillus nidulans. Images from AFM and cryo-scanning electron microscopy provided comparable information, but AFM was also able to image and physically probe living cells. AFM images showed changes in the surface ultrastructure of A. nidulans hyphae, from newly deposited walls at hyphal tips to fully mature walls, as well as additional changes at young branches arising from mature walls. Surface architecture during wall maturation correlated with changes in the relative viscoelasticity (compliance per unit applied force) of walls measured by force spectroscopy (FS) in growing A. nidulans hyphae. Growing tips showed greater viscoelasticity than mature walls, despite equal support from turgor. Branch tips had comparable viscoelasticity to hyphal tips, unlike the mature wall from which they grew. FS also revealed differences in surface hydrophilicity between newly deposited and mature walls, with the tips being more hydrophilic. The hydrophilicity of young branch tips was similar to that of hyphal tips, and different from that of mature walls. Taken together, AFM images and FS data suggest that the A. nidulans wall matures following deposition at the hyphal tip.

scholarly journals Isolation and characterization of a rough colony type of Neisseria gonorrhoeae

1977 ◽  
Vol 5 (3) ◽  
pp. 365-369
Author(s):  
N F Jacobs ◽  
S J Kraus ◽  
C Thornsberry ◽  
J Bullard
Keyword(s):  
Electron Microscopy ◽  
Neisseria Gonorrhoeae ◽  
Primary Cultures ◽  
Irregular Surface ◽  
Colony Type ◽  
Isolation And Characterization ◽  
Distinctive Morphology ◽  
Rough Form

A new colony type of Neisseria gonorrhoeae was detected in the primary cultures from 8 of 180 men with gonococcal urethritis. This colony type contrasts with those previously described by having a rough and irregular surface. In six of the eight cases, the rough form predominated. The distinctive morphology of the rough colony variant could be maintained indefinitely by selective subculture. By electron microscopy, organisms taken from rough colonies of each of the eight isolates were piliated. Antimicrobial susceptibilities of type 1 and rough clones derived from the same patients were identical for ampicillin, penicillin, tetracycline, and spectinomycin. After inoculation of rough colonies into subcutaneous chambers in mice and guinea pigs, type 1 colonies predominated in cultures of material obtained from the chambers. This new piliated colony type of N. gonorrhoeae may provide an opportunity to investigate factors other than pili that contribute to gonococcal virulence.

scholarly journals Isolation and Characterization of Protein Bodies From Developing Wheat Endosperm

1963 ◽  
Vol 16 (2) ◽  
pp. 375 ◽  
Author(s):  
Janet SD Graham ◽  
RK Morton ◽  
JK Raison
Keyword(s):  
Electron Microscopy ◽  
Gel Electrophoresis ◽  
Starch Gel Electrophoresis ◽  
Separation And Purification ◽  
Isolation And Characterization ◽  
Dense Bodies ◽  
Starch Gel ◽  
Slow Moving ◽  
Protein Components

Procedures are described for separation and purification of electron-dense bodies previously observed in intact endosperm by electron microscopy. Isolated bodies consist largely of protein. By starch-gel electrophoresis, the bodies contain predominantly slow-moving protein components similf1l' to those found in acetic acid extracts of whole endosperm.

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