Physical and Chemical Properties of Microvitellogenin
نویسنده
چکیده
Microvitellogenin belongs to a new class of low molecular weight female-specific proteins in insects. The protein is found in the hemolymph (blood) and egg of the tobacco hornworm, Manduca sexta. The isolation of microvitellogenin has been achieved by a combination of gel permeation, cation-exchange, and adsorption chromatographic steps. Microvitellogenin is synthesized by the fat body and appears in the emolymph 17 days before adult emergence, or 16 days before the onset of egg development. The protein is sequestered from the hemolymph into the egg where it accumulates to a relatively high concentration. The proteins isolated from the hemolymph and the egg are identical in their molecular weight, amino acid compositions, isoelectric points, circular dichroic spectra, immunological properties, and NH,-terminal amino acid sequence. Thus, microvitellogenin does not seem to undergo any modifications before or after it is sequestered in the egg. In solution, the protein exists in a monomeric form and has a secondary structure composed of approximately 38% a-helix, as estimated by CD analysis. The CD spectrum of microvitellogenin is unusual in that it has a strong positive band between 220 and 240 nm that may be due to contributions from the aromatic amino acid residues. Unlike the major egg yolk protein of insects, vitellogenin, microvitellogenin does not contain measurable carbohydrate or lipid, and has no immunological, chemical, or physical similarities to vitellogenin. The amino acid composition of microvitellogenin is low in cysteine, but is rich in aspartate. The sex specificity of the protein and its accumulation in the egg justifies the name microvitellogenin, first given to an analogous protein in the egg of the giant silkmoth, Hyalophora cecropia.
منابع مشابه
Influence of organic compost compounds on soil chemical and physical properties
This study was conducted to evaluate the impact of municipal waste compost and manure on soil chemical and physical properties quality and crop production in Sari city (north of Iran). In this study, the effect of compost and manure (cow and sheep) on the quality of soil organic material with experimental measurements was investigated. An experiment was conducted in a completely randomized desi...
متن کاملThe investigation of physical and chemical properties of collagenous tissue before and after ArF laser irradiation
متن کامل
Wildlife and Livestock Grazing Effects on Some Physical and Chemical Soil Properties (Case Study: Kalmand-Bahadoran Arid Rangelands of Yazd Province)
Owing to the importance and necessity of identifying soil properties in arid rangeland management, and the variableeffects of different kinds of herbivores on soil, this study compares some of the physical and chemical properties ofsoil between two regions experiencing livestock and wildlife grazing in the desert rangelands of Kalmand-Bahadoranin Yazd province. The key areas in two regions expe...
متن کاملThe Prediction of Thermo Physical, Vibrational Spectroscopy, Chemical Reactivity, Biological Properties of Morpholinium Borate, Phosphate, Chloride and Bromide Ionic Liquid: A DFT Study
In the light of computational chemistry, based on morpholinium cation-based Ionic Liquid, their different types of physical, chemical, and biological properties is highlighted. The physical properties are evaluated through the Density Functional Theory (DFT) of Molecular Mechanics and also examine the chemical and biological properties. The difference between Highest Occupied Molecular Orbital ...
متن کاملGeostatistical assessment of Pb and the related soil physical and chemical properties in near-surface soil around Sepahanshahr, Isfahan
This paper presents a survey on soil Pb concentration around Sepahanshahr town located in vicinity of Isfahan. Due to the lack of regulation and environmental education and awareness, Sepahanshahr is now a rapid growing residential area suffering from the considerable consequences of poorly regulated mining activities operating in its vicinity. The aim of this study is to explore the spatial st...
متن کامل