Primaiy structure

Proteins are macromolecules that play many roles such as serving as enzymes or components of cell membranes and muscle. The antibodies that protect against invasion by foreign substances are themselves proteins. There are twenty-odd amino acids found regularly in most naturally occurring proteins. Because of the great length of protein chains and the various sequences of amino acids, the theoretic number of possible proteins is astronomical. The amino acid sequence is referred to as the primaiy structure of a protein. The pol eptide... 

The primaiy structure of a protoin ia timply the amino acid... 

Correlating precisely defined primaiy structure with crystalline properties... 

Proteins are high molecular mass polypeptides with complex structures. The sequence of amino acids gives the primaiy structure of the protein, while the secondary and tertiary structures reveal the spatial properties of the peptide chain. The secrurdary structure takes into account the folding of polypeptide chains into domains called a-helices, jd-sheets, turns and coils, hr the ribbon representations of the protein structures illustrated in this chapter, the same colour coding is used to differentiate between... 

The primaiy oojective of the structured approach is to separate cleanly the following two aspects of the batch logic ... 

In view of the numerous advantages of POMs the development of strategies for converting them to solid catalysts is of primaiy interest. First, catalytically active POMs can be heterogenized in the form of insoluble salts using Cs, Ag, K, NH/ and some organic cations [37,49, 58-64]. Such salts possess micro/mesoporous structure and their smface area is typically in the range of 10-150 mVg. 

In contrast to the X-ray results, ab initio calculations of the isolated molecules of primary, and tertiary amides indicated that for these molecules the G+aa structure is favored. The driving force being hydrogen bonds between distal OH and C=0 groups and in the case of the primaiy amide hydrogen bonds with NH groups as donors and proximal OH as acceptors [20,22],... 

Primaiy (1°) amide (Section 22.1) An amide having the general structure RCONH2. 

Primaiy (1°) amine (Sections 21.11, 25.1) An amine having the general structure RNH2. 

Primaiy protein structure (Section 28.8A) The particular sequence of amino acids joined together by peptide bonds. 

Primaiy (1°) radical (Section 15.1) A radical having the general structure RCH2. ... 

Type III polyketide synthases represent an evolutionarily distinct sub-type, and are less structurally and catalytically complex than the type I and II enzymes. In general, the type III enzymes have no significant similarity at the primaiy sequence level to either FAS or other PKS sub-types, and likely arose via an entirely distinct evolutionary path 24). Initially, type III PKSs were designated as plant-specific , however in more recent years type III synthases have also been characterized from bacteria e.g., 28). Additionally, the presence of related sequences identified within the sequenced genomes of numerous bacterial species strongly suggests that the blueprint for type III enzymes pre-dates their adaptation for use by land plants 24,25). 

MB is known to inhibit glucose uptake by the parasite, which then depletes its stored glycogen, leading to ATP failure and death. The drug has also been shown to interact with helminthic tubulin, the structural protein of the microtubles mammalian tubulin is affected to a much lower extent. This differential effect, combined with the lack of systemic absorption, may account for the selective toxicity. It has not been established whether the tubulin effect or the interference with carbohydrate metabolism is the primaiy cytotoxic event, or what the relationship is between the two phenomena, if there is any. 

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