Pseudomonas aeruginosa

[lilsissy]

Laser microscope anyone,

www.microbelibrary.org/asmonly/details.asp?id=546&Lang=

[lilsissy]

self assembly wow
Polyester synthases: natural catalysts for plastics
Bernd H. A. REHM1
Institut für Molekulare Mikrobiologie und Biotechnologie der Westfälischen Wilhelms-Universität Münster, Corrensstrasse 3, 48149 Münster, Germany

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Polyhydroxyalkanoates (PHAs) are biopolyesters composed of hydroxy fatty acids, which represent a complex class of storage polyesters. They are synthesized by a wide range of different Gram-positive and Gram-negative bacteria, as well as by some Archaea, and are deposited as insoluble cytoplasmic inclusions. Polyester synthases are the key enzymes of polyester biosynthesis and catalyse the conversion of (R)-hydroxyacyl-CoA thioesters to polyesters with the concomitant release of CoA. These soluble enzymes turn into amphipathic enzymes upon covalent catalysis of polyester-chain formation. A self-assembly process is initiated resulting in the formation of insoluble cytoplasmic inclusions with a phospholipid monolayer and covalently attached polyester synthases at the surface. Surface-attached polyester synthases show a marked increase in enzyme activity. These polyester synthases have only recently been biochemically characterized. An overview of these recent findings is provided. At present, 59 polyester synthase structural genes from 45 different bacteria have been cloned and the nucleotide sequences have been obtained. The multiple alignment of the primary structures of these polyester synthases show an overall identity of 8–96% with only eight strictly conserved amino acid residues. Polyester synthases can been assigned to four classes based on their substrate specificity and subunit composition. The current knowledge on the organization of the polyester synthase genes, and other genes encoding proteins related to PHA metabolism, is compiled. In addition, the primary structures of the 59 PHA synthases are aligned and analysed with respect to highly conserved amino acids, and biochemical features of polyester synthases are described. The proposed catalytic mechanism based on similarities to a/b-hydrolases and mutational analysis is discussed. Different threading algorithms suggest that polyester synthases belong to the a/b-hydrolase superfamily, with a conserved cysteine residue as catalytic nucleophile. This review provides a survey of the known biochemical features of these unique enzymes and their proposed catalytic mechanism.


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Key words: biopolyester, biopolymer, catalytic

[bannanny]

I was saying in a post not long ago how much peach fuzz I have on my face now. It's more at the edges of my face around the hairline, but it looks terrible in the right light.

At the second link in your first post sissy, I found it ironic that listed under "see similar items" the links were to plastics. genetic plants and polymer chains.

Why is it so dam important for these scientists to invent devices for drug delivery in the first place? What was ever so wrong with taking a pill or having an IV inserted to deliver them thru our body's natural way of delivering them? They must be so bored with everything that's natural... if they only knew how beautiful natural is.

The more I read tho, the more I just wanna send them all to an island of their own on some other planet... somewhere where they'll leave us alone anyway. They can play God somewhere else ya know? I don't want any of them in my world anymore... but I think it's too late to even want.

hugs ~~ bannannas