Biomaterial Database

Interactions between clay minerals and siderophores affect the respiration of Histoplasma capsulatum. 1986

S Lavie, and G Stotzky

The reduction in the respiration of Histoplasma capsulatum in broth culture caused by montmorillonite appeared to be the result, in part, of the interference by the clay with the iron nutrition of the fungus. This interference was apparently the result of the adsorption by the clay of the iron-transporting siderophore (deferricoprogen B) produced by the fungus, as the reduction in respiration was partially alleviated by the addition of foreign siderophores. Neither kaolinite nor attapulgite (palygorskite) appeared to adsorb significant amounts of the siderophores, probably because of the low cation exchange capacity and specific surface area of kaolinite and the inaccessibility of adsorption sites in the fibrous attapulgite. These observations, in addition to the adhesion of montmorillonite to the hyphae, suggest mechanisms that may explain the discrete geographic distribution of this fungus, which is pathogenic to humans and which has been isolated essentially only from soils that do not contain montmorillonite.

UI	MeSH Term	Description	Entries
D007502	Iron Chelating Agents	Organic chemicals that form two or more coordination links with an iron ion. Once coordination has occurred, the complex formed is called a chelate. The iron-binding porphyrin group of hemoglobin is an example of a metal chelate found in biological systems.	Iron Chelates,Agents, Iron Chelating,Chelates, Iron,Chelating Agents, Iron
D007616	Kaolin	The most common mineral of a group of hydrated aluminum silicates, approximately H2Al2Si2O8-H2O. It is prepared for pharmaceutical and medicinal purposes by levigating with water to remove sand, etc. (From Merck Index, 11th ed) The name is derived from Kao-ling (Chinese: "high ridge"), the original site. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Kaolinite
D008274	Magnesium	A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D003676	Deferoxamine	Natural product isolated from Streptomyces pilosus. It forms iron complexes and is used as a chelating agent, particularly in the mesylate form.	Desferrioxamine,Deferoxamine B,Deferoxamine Mesilate,Deferoxamine Mesylate,Deferoxamine Methanesulfonate,Deferoximine,Deferrioxamine B,Desferal,Desferioximine,Desferrioxamine B,Desferrioxamine B Mesylate,Desferroxamine,Mesilate, Deferoxamine,Mesylate, Deferoxamine,Mesylate, Desferrioxamine B,Methanesulfonate, Deferoxamine
D006658	Histoplasma	A mitosporic Onygenales fungal genus causing HISTOPLASMOSIS in humans and animals. Its single species is Histoplasma capsulatum which has two varieties: H. capsulatum var. capsulatum and H. capsulatum var. duboisii. Its teleomorph is AJELLOMYCES capsulatus.	Ajellomyces capsulatus,Cryptococcus capsulatus,Emmonsiella capsulata,Histoplasma capsulatum,Histoplasmas
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000077215	Clay	A naturally-occurring rock or soil constituent characterized by particles with a diameter of less than 0.005 mm. It is composed primarily of hydrous aluminum silicates, trace amounts of metal OXIDES, and organic matter.	Halloysite,Clays,Halloysites
D000327	Adsorption	The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.	Adsorptions
D000538	Aluminum Silicates	Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)	Aluminum Silicate,Silicate, Aluminum,Silicates, Aluminum