- #1
snorkack
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We on extant Earth meet a certain choice of biopolymers.
Structural biopolymers include proteins. Most of the rest of the structural biopolymers are polysaccharides. But with one conspicuous exception: lignin which is a polymer of p-propylphenols.
The most common structural polysaccharide on extant Earth is cellulose - which is 1-6 glycoside bonded glucose.
But cellulose is by no means the only polysaccharide on extant Earth.
For example, hemicellulose is also abundant structural polysaccharide, yet it also contains mannose, galactose, xylose and arabinose... and hemicellulose is not even a carbohydrate because it contains some rhamnose (a deoxy sugar) and uronic acids (glucuronic and galacturonic acid) with no guarantee of rhamnose being balanced with uronic acids.
Pectins are largely based on galacturonic acid (so not carbohydrates either) but also contain xylose, apiose, rhamnose, galactose, arabinose... and many methyl esters.
So... if an alien life form has biochemistry largely familiar on Earth but produces a structural polysaccharide unknown on Earth, what can we say about its biomechanical properties, biosynthesis and remodelling based on its structure?
Structural biopolymers include proteins. Most of the rest of the structural biopolymers are polysaccharides. But with one conspicuous exception: lignin which is a polymer of p-propylphenols.
The most common structural polysaccharide on extant Earth is cellulose - which is 1-6 glycoside bonded glucose.
But cellulose is by no means the only polysaccharide on extant Earth.
For example, hemicellulose is also abundant structural polysaccharide, yet it also contains mannose, galactose, xylose and arabinose... and hemicellulose is not even a carbohydrate because it contains some rhamnose (a deoxy sugar) and uronic acids (glucuronic and galacturonic acid) with no guarantee of rhamnose being balanced with uronic acids.
Pectins are largely based on galacturonic acid (so not carbohydrates either) but also contain xylose, apiose, rhamnose, galactose, arabinose... and many methyl esters.
So... if an alien life form has biochemistry largely familiar on Earth but produces a structural polysaccharide unknown on Earth, what can we say about its biomechanical properties, biosynthesis and remodelling based on its structure?