LOCATION OF PROTEINASE IN CELLS OF A SPECIES OF MICROCOCCUS

1962 ◽  
Vol 8 (5) ◽  
pp. 785-794 ◽  
Author(s):  
I. J. McDonald
Keyword(s):  
Sodium Chloride ◽  
Cell Membrane ◽  
Yeast Extract ◽  
Membrane Fraction ◽  
Culture Supernatant ◽  
Cytoplasmic Membrane ◽  
Cell Envelope ◽  
Sonic Treatment ◽  
Added Salt ◽  
In Cells

Micrococcus sp. (ATCC No. 407) grown in tryptone yeast extract broth produced proteinase active against casein. In broth containing 2.0% sodium chloride, about 90% of the proteinase was in the culture supernatant; in broth without added salt, about 66% was associated with the cells. When such cells were washed with 2% sodium chloride, about one-half the associated proteinase was released. Presumably this saline-extractable portion of the proteinase is loosely held at the ceil surface, possibly by ionic linkages. A further yield of proteinase could be obtained from saline-washed cells by treatments that ruptured the cells or altered the permeability of the cell membrane. This so-called bound proteinase became accessible to the substrate, but was not liberated into the suspending medium on lysozyme treatment of saline-washed cells. When lysozyme-treated cells were fractionated, the proteinase was found with the cytoplasmic membrane fraction. During sonic treatment of saline-washed cells, the bound. proteinase was released without appreciable disintegration of the cell envelope suggesting that it may not be an integral part of the cell membrane.

scholarly journals Formation of Giant Lipid Vesicles in the Presence of Nonelectrolytes—Glucose, Sucrose, Sorbitol and Ethanol

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 945
Author(s):  
Qiong Wang ◽  
Ning Hu ◽  
Jincan Lei ◽  
Qiurong Qing ◽  
Jing Huang ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Cell Membrane ◽  
Lipid Membranes ◽  
Volume Fraction ◽  
Hydrodynamic Force ◽  
Lipid Vesicles ◽  
Ethanol Solution ◽  
Sugar Solution ◽  
Ethanol Content ◽  
Membrane Models

Lipid vesicles, especially giant lipid vesicles (GLVs), are usually adopted as cell membrane models and their preparation has been widely studied. However, the effects of some nonelectrolytes on GLV formation have not been specifically studied so far. In this paper, the effects of the nonelectrolytes, including sucrose, glucose, sorbitol and ethanol, and their coexistence with sodium chloride, on the lipid hydration and GLV formation were investigated. With the hydration method, it was found that the sucrose, glucose and sorbitol showed almost the same effect. Their presence in the medium enhanced the hydrodynamic force on the lipid membranes, promoting the GLV formation. GLV formation was also promoted by the presence of ethanol with ethanol volume fraction in the range of 0 to 20 percent, but higher ethanol content resulted in failure of GLV formation. However, the participation of sodium chloride in sugar solution and ethanol solution stabilized the lipid membranes, suppressing the GLV formation. In addition, the ethanol and the sodium chloride showed the completely opposite effects on lipid hydration. These results could provide some suggestions for the efficient preparation of GLVs.

Interaction of Gram-Negative Bacteria with the Lysosomal Fraction of Polymorphonuclear Leukocytes II. Changes in the Cell Envelope of Escherichia coli

1970 ◽  
Vol 1 (3) ◽  
pp. 311-318
Author(s):  
D. Friedberg ◽  
I. Friedberg ◽  
M. Shilo
Keyword(s):  
Escherichia Coli ◽  
Polymorphonuclear Leukocytes ◽  
Cytoplasmic Membrane ◽  
Morphological Changes ◽  
Cell Envelope ◽  
Gram Negative Bacteria ◽  
Intact Cells ◽  
Lysosomal Fraction ◽  
E Coli ◽  
Absorbing Material

Interaction of lysosomal fraction with Escherichia coli caused damage to the cell envelope of these intact cells and to the cytoplasmic membrane of E. coli spheroplasts. The damage to the cytoplasmic membrane was manifested in the release of 260-nm absorbing material and β-galactosidase from the spheroplasts, and by increased permeability of cryptic cells to O -nitrophenyl-β- d -galactopyranoside; damage to the cell wall was measured by release of alkaline phosphatase. Microscope observation showed morphological changes in the cell envelope.

Sensitivity of normal and mutant strains of Escherichia coli to actinomycin-D

1972 ◽  
Vol 18 (6) ◽  
pp. 909-915 ◽  
Author(s):  
A. P. Singh ◽  
K.-J. Cheng ◽  
J. W. Costerton ◽  
E. S. Idziak ◽  
J. M. Ingram
Keyword(s):  
Escherichia Coli ◽  
Cell Wall ◽  
Wild Type Strain ◽  
Actinomycin D ◽  
Cytoplasmic Membrane ◽  
Cell Envelope ◽  
Coli Strain ◽  
Wild Type ◽  
Mutant Strains ◽  
In The Wild

The site of the cell barrier to actinomycin-D uptake was studied using a wild-type Escherichia coli strain P and its cell envelope-defective filamentous mutants, strains 6γ and 12γ, both of which 'leak' β-galactosidase and alkaline phosphatase into the medium during growth indicating both membrane and cell-wall defects. Actinomycin-D entered the cells of these two mutant strains as evidenced by the inhibition of both 14C-uracil incorporation and synthesis of the induced β-galactosidase system. Under similar conditions, no inhibition occurred in the wild-type strain and its sucrose-lysozyme prepared spheroplasts. Actinomycin-D did, however, inhibit the above-mentioned systems in the wild-type sucrose-lysozyme spheroplasts prepared in the presence of 2 mM EDTA. The experimental data indicate that although the cell wall may act as a primary barrier or sieve to actinomycin-D, the cytoplasmic membrane should be considered the final and determinative barrier to this antibiotic.

scholarly journals Changes in Cell Membrane and Cellular Lipids in Apoptotic Cells Induced by Dolichyl Phosphate Differ from Findings in Cells Induced by Etoposide.

2002 ◽  
Vol 51 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Akiko HORIUCHI ◽  
Etsuko YASUGI ◽  
Chizu IWASAKI ◽  
Keiji FUJIMOTO ◽  
Mieko OSHIMA
Keyword(s):  
Cell Membrane ◽  
Apoptotic Cells ◽  
Dolichyl Phosphate ◽  
Cellular Lipids ◽  
In Cells

Ultrastructure of the cell envelope and septation process in Caryophanon latum as revealed by thin section and freeze-etching techniques

1974 ◽  
Vol 20 (10) ◽  
pp. 1435-1442 ◽  
Author(s):  
W. C. Trentini ◽  
H. E. Gilleland Jr.
Keyword(s):  
Cytoplasmic Membrane ◽  
External Surface ◽  
Cell Envelope ◽  
Optimal Conditions ◽  
Structural Detail ◽  
Cross Sectional ◽  
External Wall ◽  
Thin Sectioning ◽  
Freeze Etching ◽  
Peptidoglycan Layer

With optimal conditions of thin-sectioning and freeze-etching, the cell wall of Caryophanon latum was composed of a thick peptidoglycan layer plus two external wall layers. The freeze-etched appearance of the external surface of the outer layer was smooth and lacked structural detail. The numerous cross septa within a trichome were formed by the symmetrical and concurrent ingrowth of the cytoplasmic membrane and the peptidoglycan layer. The site of septum initiation was identifiable by a dart-shaped ingrowth of the peptidoglycan layer rather than by the presence of a mesosome. However, small simple mesosomes were occasionally seen associated with the developing septum. The peptidoglycan in the septum had thickened to at least double the thickness of the wall peptidoglycan layer by the time of septum completion. The external wall layers did not participate in septum formation but did participate in trichome separation. The separation of the septal peptidoglycan was completed during the early ingrowth of the external wall layers. A unique cross-sectional view of a developing septum closing like an iris diaphragm as seen in a freeze-etched preparation was observed.

scholarly journals The High-Molecular-Weight Cytochrome c Cyc2 of Acidithiobacillus ferrooxidans Is an Outer Membrane Protein

2002 ◽  
Vol 184 (1) ◽  
pp. 313-317 ◽  
Author(s):  
Andrés Yarzábal ◽  
Gaël Brasseur ◽  
Jeanine Ratouchniak ◽  
Karen Lund ◽  
Danielle Lemesle-Meunier ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Outer Membrane ◽  
High Molecular Weight ◽  
Acidithiobacillus Ferrooxidans ◽  
Ferrous Iron ◽  
Membrane Fraction ◽  
Cytoplasmic Membrane ◽  
Respiratory Pathway ◽  
Membrane Components ◽  
Membrane Level

ABSTRACT A high-molecular-weight c-type cytochrome, Cyc2, and a putative 22-kDa c-type cytochrome were detected in the membrane fraction released during spheroplast formation from Acidithiobacillus ferrooxidans. This fraction was enriched in outer membrane components and devoid of cytoplasmic membrane markers. The genetics, as well as the subcellular localization of Cyc2 at the outer membrane level, therefore make it a prime candidate for the initial electron acceptor in the respiratory pathway between ferrous iron and oxygen.

Structural changes in cells of Clostridium perfringens infected with a short-tailed bacteriophage

1971 ◽  
Vol 17 (3) ◽  
pp. 397-402 ◽  
Author(s):  
David E. Bradley ◽  
Judith F. M. Hoeniger
Keyword(s):  
Electron Microscope ◽  
Clostridium Perfringens ◽  
Structural Changes ◽  
Cell Envelope ◽  
Cell Lysis ◽  
Cell Periphery ◽  
Normal Cells ◽  
Phage Growth ◽  
Cooked Meat ◽  
In Cells

A culture of Clostridium perfringens strain 80 in cooked meat broth contained three types of cell: normal, long, and small round cells. The process of phage maturation and cell lysis was studied in all three forms using the electron microscope. In normal cells, the nucleoplasm first enlarged, then small clear areas, slightly larger than intracellular phages, appeared mainly around the cell periphery. The nucleoplasm dispersed and mature phage particles were formed. Subsequent lysis was caused by the breaking off of portions of the cell envelope leaving holes for the release of the contents. Long cells were also able to support phage growth.

Sign in / Sign up

Export Citation Format

Share Document