Classification mammals

Ceramidases are enzymes that cleave the N-acyl linkage of Cer into SPH and free fatty acid. They are an emerging class of enzymes composed of multiple isoforms. Historically, these isoforms have been classified as acid, neutral or alkaline, based on the pH optimum of their activities although some isoforms show activity in a broad range. With the recent cloning of several isoforms from yeast, bacteria, and mammals, a genetical distinction and classification of these enzymes can now be employed. 

The catch-all classification for other toxins falls in this group. Generally, these compounds are diverse and often chemically unrelated. As diverse as their chemical natures are, so are the diversity of their effects in mammals when ingested or when physical contact is made. Phenolics are one major component of this group, and are themselves very diverse. The definition of a phenolic is an alcohol or hydroxy group coupled to an aromatic ring. 

Most marine biotoxications are caused by fishes, but turtles and mammals have been incriminated in rare instances. A tentative classification of ichthyotoxic fishes is as follows ... 

This chapter considers the classification, nomenclature, primary structure, and chemical and physical properties of the individual protein as they occur in the milk from the genus Bos. While some studies have been done of the proteins of the milk of other mammals, bovine milk, due to its commercial importance, has been most extensively investigated. A more comprehensive treatment of the subject is in the two-volume treatise on the chemistry and molecular biology of the milk proteins edited by McKenzie (1970, 1971A). Other reviews are Whitney (1977), Brunner (1981), and Swaisgood (1982). 

The inability of mammals to synthesize all of the amino acids they require has led to the classification of amino acids as essential and nonessential. Conceptually this distinction seems clear. Practically speaking, it turns out to be more complex to designate essential amino acids. An essential amino acid, in this classification, means one that must be supplied in the diet if the organism is to maintain a positive nitrogen balance. As we will see, the absence of a de novo pathway for the biosynthesis of an amino acid does... 

Qb-, Qc- and R-SNAREs (Bock and Scheller 2001). Following this classification, syntaxin 1A, SNAP-25, and synaptobrevin 2 represent the Qa-, Qb- and Qc-, and R-SNAREs, respectively (Fasshauer et al. 1998). It turned out later that actually all functional SNARE complexes assigned to trafficking steps in yeast and mammals have a QaQbQcR-composition (Hong 2005 Jahn and Scheller 2006). 

We have many times emphasized that all life has very similar chemistry. Indeed, in terms of biochemistry there is little need for the classifications of mammals, plants, and so on. There is only one important division—into prokaryotes and eukaryotes. Prokaryotes, which include bacteria, evolved first and have simple cells with no nucleus. Eukaryotes, which include plants, mammals, and all... 

Table 1 Classification of collagen in mammals Known and estimated information about collagen...

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