Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2000 Jan;182(2):257-63.
doi: 10.1128/JB.182.2.257-263.2000.

Bacteria are not what they eat: that is why they are so diverse

D Parke  1 , D A D'Argenio, L N Ornston
Affiliations
Review

Bacteria are not what they eat: that is why they are so diverse

D Parke et al. J Bacteriol. 2000 Jan.
No abstract available

PubMed Disclaimer

Figures

FIG. 1
FIG. 1
Central reactions of the protocatechuate branch of the β-ketoadipate pathway in bacteria. Metabolic steps or sequences are represented by designations for the associated genes. Plant products such as quinate and phenylpropenoid compounds (ferulate, caffeate, and coumarate) are metabolized to protocatechuate (in the box with the thin black border). Enzymes encoded by the pca genes convert protocatechuate to common metabolites. The intermediate carboxymuconate (in the box with the thick black border) is very toxic, and cells lacking a functional pcaB fail to grow when protocatechuate or metabolic precursors of this compound are added to growth media. Secondary mutations preventing formation of carboxymuconate from aromatic compounds can be selected, which has facilitated genetic analysis of vanAB, pobA, and pcaHG. Exposure of cells to high concentrations of protocatechuate also impedes growth, and characterization of strains resisting this toxicity led to discovery of functions associated with the transporters VanK and PcaK in Acinetobacter. The β-ketoadipate transporter encoded by pcaT is found in fluorescent Pseudomonas species and has no known counterpart in Acinetobacter.
FIG. 2
FIG. 2
Organization of genes for protocatechuate catabolism in P. putida and Acinetobacter. The structures of inducing metabolites are shown. Arrows indicate the transcriptional activator genes pcaR and pcaU. They encode proteins that are similar in sequence and bind to similar operators, but the proteins respond to different inducers.
FIG. 3
FIG. 3
Compartmentation of quinate catabolism in Acinetobacter. Mutations blocking both pcaK and vanK impede growth with quinate, and cells containing these mutations accumulate protocatechuate in the growth medium. Thus, in accord with earlier suggestions, the initial steps in quinate utilization appear to take place on the outer surface of the inner cell membrane. Not shown in the figure is shikimate which is catabolized directly to dehydroshikimate by QuiA. Compartmentation keeps catabolic enzymes that act upon shikimate and dehydroshikimate physically separate from enzymes that must supply these compounds as biosynthetic intermediates under all growth conditions.
FIG. 4
FIG. 4
Frequent mutations causing loss or gain of vanK function in Acinetobacter. The gene acquired a homopolymeric G tract during its evolutionary divergence from related transporters. Evidently slippage during replication can cause loss of a G residue from the tract. This mutation introduces a stop codon directly downstream from the G tract. The deletion reverts readily, so most populations of the Acinetobacter cell line have a mixture of wild-type cells and cells containing the deletion mutation.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Andersson D I, Slechta E S, Roth J R. Evidence that gene amplification underlies adaptive mutability of the bacterial lac operon. Science. 1998;282:1133–1135. - PubMed
    1. Baumann P. Isolation of Acinetobacter from soil and water. J Bacteriol. 1968;96:39–42. - PMC - PubMed
    1. Baumann P, Doudoroff M, Stanier R Y. A study of the Moraxella group. II. Oxidative-negative species (genus Acinetobacter) J Bacteriol. 1968;95:520–541. - PMC - PubMed
    1. Bernards M A, Lewis N G. The macromolecular aromatic domain in suberized tissue: a changing paradigm. Phytochemistry. 1998;47:915–933. - PubMed
    1. Canovas J L, Ornston L N, Stanier R Y. Evolutionary significance of metabolic control systems. The β-ketoadipate pathway provides a case history in bacteria. Science. 1967;156:1695–1699. - PubMed

Publication types

MeSH terms

LinkOut - more resources