EFFECT OF ACID HYDROLYZATES OF AGAR ON THE GROWTH OF ESCHERICHIA COLI

1959 ◽  
Vol 5 (6) ◽  
pp. 589-593 ◽  
Author(s):  
W. Yaphe
Keyword(s):  
Escherichia Coli ◽  
Acid Hydrolysis ◽  
Degradation Product ◽  
Inhibitory Effect ◽  
Degree Of Hydrolysis ◽  
Mild Acid Hydrolysis ◽  
Heat Labile ◽  
Hydrolysis Of ◽  
Different Levels ◽  
Mild Acid

Studies were carried out to determine the effect of the products of acid hydrolysis of agar on the growth of Escherichia coli. The inhibitory effect was associated with the degree of hydrolysis of the agar. This inhibition has been obtained at two very different levels of concentration. When the hydrolysis was complete, the inhibitory pattern was similar to that of 5-hydroxymethyl-2-furaldehyde. Under conditions of mild acid hydrolysis, the inhibitory effect was caused by a heat-labile degradation product of 3,6-anhydro-L-galactose.

FURTHER STUDIES ON THE ANTIGENS OF ESCHERICHIA COLI O26:B6

1966 ◽  
Vol 12 (2) ◽  
pp. 249-254
Author(s):  
Joseph E. McDade ◽  
W. Robert Bailey
Keyword(s):  
Escherichia Coli ◽  
Acid Hydrolysis ◽  
Molecular Complex ◽  
Cell Suspensions ◽  
Soluble Antigen ◽  
Mild Acid Hydrolysis ◽  
Hydrolysis Of ◽  
Mild Acid

The effect of heat on the O and B antigens of Escherichia coli serotype O26:B6 was studied. Aliquots of cell suspensions containing 1.5 × 1010 cells/ml were heated at 55, 65, 75, 85, and 100 °C, respectively, for 1 hour. The heated cells were centrifuged and the precipitinogen titer determined using O and OB antisera. The supernatants from cell suspensions heated at the higher temperatures contained proportionately more of the soluble antigen than those heated at the lower temperatures.Gel diffusion tests of the supernatants showed that both O and B antigens were released when cells were heated. Mild acid hydrolysis of a supernatant increased the B reactivity of that supernatant and slightly enhanced the O reaction. It was concluded from this study that the O and B antigens exist as a molecular complex; heating releases the B component from the complex and causes the increased agglutination with O antiserum.

Sequential Enzymatic and Mild-Acid Hydrolysis of By-Product of Carrageenan Process from Kappaphycus alvarezii

2019 ◽  
Vol 12 (2) ◽  
pp. 419-432 ◽  
Author(s):  
Fernando Roberto Paz-Cedeno ◽  
Eddyn Gabriel Solórzano-Chávez ◽  
Levi Ezequiel de Oliveira ◽  
Valéria Cress Gelli ◽  
Rubens Monti ◽  
...  
Keyword(s):  
Acid Hydrolysis ◽  
Kappaphycus Alvarezii ◽  
Mild Acid Hydrolysis ◽  
Hydrolysis Of ◽  
Mild Acid

scholarly journals IMMUNOCHEMICAL STUDIES ON BLOOD GROUPS

1971 ◽  
Vol 133 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Ten Feizi ◽  
Elvin A. Kabat ◽  
Giuseppe Vicari ◽  
Byron Anderson ◽  
W. Laurence Marsh
Keyword(s):  
Acid Hydrolysis ◽  
Blood Group ◽  
Ovarian Cyst ◽  
Periodate Oxidation ◽  
Human Saliva ◽  
Mild Acid Hydrolysis ◽  
Group B ◽  
Hydrolysis Of ◽  
Substantial Heterogeneity ◽  
Mild Acid

A partially purified blood group-like substance obtained from milk showed I activity with 2 of 21 anti-I sera. With these antisera, certain human ovarian cyst substances considered to be precursors of the A, B, H, Lea, and Leb substances also showed I activity comparable to the milk material. Strong I activity could be produced by one-stage periodate oxidation and Smith degradation of human ovarian cyst A and B substances, or of hog mucin A + H substance, or by mild acid hydrolysis of human saliva or ovarian cyst blood group B substance. The two sera indicate that I specificity appears at intermediate stages in the biosynthesis of the A, B, H, Lea, and Lea substances. Anti-I sera differ strikingly in their specificities, indicating substantial heterogeneity of the I determinants.

The Synthesis of Trisubstituted Enol Ethers and of Methyl Ketones from Ketones

1973 ◽  
Vol 51 (6) ◽  
pp. 981-983 ◽  
Author(s):  
Gilles Caron ◽  
Jean Lessard
Keyword(s):  
Acid Hydrolysis ◽  
Hydroxy Acid ◽  
Reliable Method ◽  
Acid Salt ◽  
Methyl Ketones ◽  
Enol Ether ◽  
Mild Acid Hydrolysis ◽  
Enol Ethers ◽  
Hydrolysis Of ◽  
Mild Acid

A reliable method for the synthesis of trisubstituted enol ethers (and of the corresponding methyl ketones) is described involving the condensation of the α-lithiated 2-methoxypropionic acid salt with a ketone to give a β-hydroxy acid, the cyclization to a β-lactone which is then decarboxylated (and mild acid hydrolysis of the enol ether).

scholarly journals Biosynthesis of dermatan sulphate. Defructosylated Escherichia coli K4 capsular polysaccharide as a substrate for the d-glucuronyl C-5 epimerase, and an indication of a two-base reaction mechanism

1996 ◽  
Vol 313 (2) ◽  
pp. 589-596 ◽  
Author(s):  
Helgi H. HANNESSON ◽  
Åsa HAGNER-McWHIRTER ◽  
Kerstin TIEDEMANN ◽  
Ulf LINDAHL ◽  
Anders MALMSTRÖM
Keyword(s):  
Escherichia Coli ◽  
Reaction Mechanism ◽  
Acid Hydrolysis ◽  
Capsular Polysaccharide ◽  
Glucuronic Acid ◽  
Microsomal Enzyme ◽  
Dermatan Sulphate ◽  
Mild Acid Hydrolysis ◽  
Mild Acid ◽  
Escherichia Coli K4

The capsular polysaccharide from Escherichia coli K4 consists of a chondroitin {[GlcA(β1→3)GalNAc(β1→4)]n} backbone, to which β-fructofuranose units are linked to C-3 of D-glucuronic acid (GlcA) residues. Removal of the fructose units by mild acid hydrolysis provided a substrate for the GlcA C-5 epimerase, which is involved in the generation of L-iduronic acid (IdoA) units during dermatan sulphate biosynthesis. Incubation of this substrate with solubilized fibroblast microsomal enzyme in the presence of 3H2O resulted in the incorporation of tritium at C-5 of hexuronyl units. A Km of 67×10-6 M hexuronic acid (equivalent to disaccharide units) was determined, which is similar to that (80×10-6 M) obtained for dermatan (desulphated dermatan sulphate). Vmax. was about 4 times higher with dermatan than with the K4 substrate. A defructosylated K4 polysaccharide isolated after incubation of bacteria with D-[5-3H]glucose released 3H2O on reaction with the epimerase, and thus could be used to assay the enzyme. Incubation of a K4 substrate with solubilized microsomal epimerase for 6 h in the presence of 3H2O resulted in the formation of about 5% IdoA and approximately equal amounts of 3H in GlcA and IdoA. A corresponding incubation of dermatan yielded approx. 22% GlcA, which contained virtually all the 3H label. These results are tentatively explained in terms of a two-base reaction mechanism, involving a monoprotic L-ido-specific base and a polyprotic D-gluco-specific base. Most of the IdoA residues generated by the enzyme occurred singly, although some formation of two or three consecutive IdoA-containing disaccharide units was observed.

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