Transcript Managing people in sport organisations: A strategic human

Xylose: is a large component of plant cell walls
FIGURE 13.2
Pathway Engineering for Xylose Utilization—Genes
Xylose must be degraded by a specific set of reactions before its conversion to alcohol. Two genes
are necessary for the initial xylose degradation, xylA and xylB. The XylA protein converts xylose to
xylulose, and XylB phosphorylates this to form xylulose 5-phosphate. The two genes are carried on
shuttle plasmids and transformed into bacteria such as Zymomonas.
Biotechnology by Clark and Pazdernik
Copyright © 2012 by Academic Press. All rights reserved.
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FIGURE 13.6
Disruption of inaZ Prevents Ice Nucleation
Cell surface proteins of P. syringae provide a nucleation point for ice. The inaZ gene encodes an icenucleating protein. Under freezing temperatures, wild-type P. syringae allow ice crystals to form,
disrupting any plant tissues the bacteria are on or within. If the inaZ gene is disrupted, the P. syringae
mutant will not nucleate any ice crystals, allowing the water to supercool.
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Copyright © 2012 by Academic Press. All rights reserved.
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FIGURE 13.8
Similar Reactions of Naphthalene and Indole
When naphthalene (top) is attacked by an oxygenase, two hydroxyls are added to form its diol. The
same oxygenase attacks the indole ring because this is similar to naphthalene. The indoxyl oxidizes
spontaneously into indigo, which is blue. The indigo ring system can have alternative groups attached
at the positions shown as X. If X is hydrogen, the molecule is indigo itself, but if X is bromine, the
molecule becomes more purple than blue and is called Tyrian purple.
Biotechnology by Clark and Pazdernik
Copyright © 2012 by Academic Press. All rights reserved.
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FIGURE 13.18
Biosynthesis of b-Lactam Antibiotics
When certain molds grow on agar originally covered with bacteria, a clear zone appears around the
mold where no bacteria are able to grow. The clearing is due to release of antibiotics such as penicillin
and cephalosporin C from the mold.
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Copyright © 2012 by Academic Press. All rights reserved.
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FIGURE 13.19
Engineered Pathway to 7-ACA
To engineer new antibacterial compounds, cephalosporin C must be converted into 7aminocephalosporanic acid (7-ACA). The enzymes involved in this conversion are d-amino acid
oxidase and cephalosporin acylase. The genes for these enzymes have been isolated, cloned, and
expressed in different bacteria, as well as in molds producing cephalosporin C itself.
Biotechnology by Clark and Pazdernik
Copyright © 2012 by Academic Press. All rights reserved.
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