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J Ortigoza-Ferado

Publications and source records attributed to J Ortigoza-Ferado.

8 recordsLinked to original sources
PubMed1984

Paraoxon hydrolysis in human serum mediated by a genetically variable arylesterase and albumin.

Gel filtration chromatography resolves human serum paraoxonase into two fractions: (1) a high molecular weight fraction that is completely inhibited by EDTA and coelutes with arylesterase (E.C.3.1.1.2); and (2) a second fraction that is closely associated with albumin, is only partially inhibited by EDTA, and has relatively little arylesterase activity under the assay conditions used. The activity of the high molecular weight fraction is stimulated by NaCl, whereas the albumin associated activity is partially inhibited by NaCl and is not present in serum derived from an analbuminemic individual. Our data suggest that albumin itself, rather than a protein bound to or cofractionating with albumin, mediates paraoxonase activity. The variation in levels of the activity of the nonalbumin, high molecular weight enzyme is responsible for the observed polymorphism of paraoxonase activity in human serum or plasma. An optimal assay of polymorphic paraoxonase activity should be based on activity measurements of the nonalbumin fraction. It is considered likely that only the nonalbumin fraction is responsible for in vivo hydrolysis of paraoxon.

Aryldialkylphosphatase↗
PubMed1968

Phosphate dependence of monosaccharide transport in Nocardia.

Uptake of the monosaccharides d-glucose and d-mannose by Nocardia asteroides and N. brasiliensis is dependent on the presence of an adequate phosphate concentration in the environment. When phosphate is replaced by solutions of sodium chloride or potassium chloride of identical ionic strength, there is no sugar uptake. In the presence of iso-osmolar concentrations of sodium arsenate, there is, however, sugar uptake activation. When nonmetabolizable 3-O-methyl d-glucose is used, most of the sugar taken up can be shown to be in the cell at a concentration never exceeding that of the external medium. Phosphate, or arsenate, seems to be essential for the actual migration of the sugar through the cell envelope. The transport of the nonmetabolizable 3-O-methyl glucose also requires phosphate, and the transport seems to be of a type that does not require energy.

Arsenic↗
PubMedDate not supplied

[Classification of Klebsiella strains with lectins].

Fourteen different plant seeds were used to obtain lectins which in turn were used to agglutinate 72 different serological strains of Klebsiella. The results were used to design a scheme which distinguishes 62 serotypes (91.6%) with a unique agglutination pattern with lectins. Two pairs of strains as well as two sets of three strains gave the same patterns. This procedure is useful as an alternative in the identification of strains for epidemiological purposes.

Agglutination Tests↗
PubMedDate not supplied

[Biological flow tracers: growth and survival of Bacillus subtilis 65-8 under environmental stress].

Microbial flow tracers are presently limited to a strain of Bacillus globigii and a few highly specific bacteriophages. Bacillus subtilis 65-8 produces a black pigment as part of the primary metabolism under minimal nutritional conditions, with glucose as the sole carbon and energy source. This work shows that Bacillus subtilis 65-8 spores are thermostable (55 degrees C during 150 días), halotolerant (they germinate and grow in an enriched medium with up to 12% NaCl), persistent in a system of sand-soil and sewage, even in the presence of added commercial oil derivatives (kerosene, leaded gasoline and unleaded diesel), they are capable to move through porous systems even as the liquids, viscous as they may be, move through. Moreover, spores were resistant to the presence of autochtonous microorganisms in sewage, where we did not detect any other organism with differential characteristics like our strain (black pigment production in minimal medium) which could interfere with the identification of our biological flow tracer. The characteristics of Bacillus subtilis 65-8 make it a suitable biological flow tracer.

Bacillus subtilis↗