Microbial Biotechnology
Fundamentals of Applied
Microbiology,
Second Edition
Chapter 1:
Picturing Distributions with Graphs
Copyright © 2007 by Alexander N. Glazer and Hiroshi Nikaido
Alexander N. Glazer and
Hiroshi Nikaido

FIGURE-01-01: Repeating unit of the polysaccharide backbone of the peptidoglycan layer in the cell wall of bacteria.

FIGURE 01-02: Membrane lipids of bacteria and eukaryotes are glycerol esters of straight-chain fatty acids such as palmitate.
Archaeal membrane lipids are diethers or tetraethers in which the glycerol unit is linked by an ether link to phytanols, branched-chain
hydrocarbons. Moreover, the configuration about the central carbon of the glycerol unit is D in the ester-linked lipids but L in the
ether-linked lipids. R is phosphate or phosphate esters in phospholipids and sugars in glycolipids.

FIGURE 01-03: Electron micrographs of bacterial cell walls. (A) Gram-positive, Arthrobacter crystallopoietes. Magnification, 126,000×.
(B) Gram-negative, Leucothrix mucor. Magnification, 165,000×. [Reproduced with permission from Brock, T. D., and Madigan, M. T.
(1988). Biology of Microorganisms, 5th Edition, Englewood Cliffs, NJ: Prentice Hall, Figure 3.22.]

FIGURE 01-04: Overall equation for the fermentation reaction sequence, in which glucose is
converted to lactic acid (homolactic fermentation).

FIGURE 01-05: Predicted secondary structure of 16S
rRNA. [Data from http://www.rna.icmb.utexas.edu/ and
Cannone, J. J., Subramanian, S., Schnare, M. N., Collett,
J. R., D’Souza, L. M., Du, Y., Feng, B., Lin, N.,
Madabusi, L. V., Muller, K. M., Pande, N., Shang, Z., Yu,
N., and Gutell, R. R. (2002). The comparative RNA
web (CRW) site: an online database of comparative
sequence and structure information for ribosomal, intron,
and other RNAs. BMC Bioinformatics, 3, 2; correction:
BMC Bioinformatics, 3, 15.]

FIGURE 01-06: A two-dimensional projection of the phylogenetic tree of the major prokaryotic groups. Groups that lie close to
together are more likely to have a recent common ancestry than are those that are well separated. The dashed lines in the time
dimension below the plane indicate the still uncertain evolutionary origins of these groups. The computational procedure used to
generate such
two-dimensional projections of the genomic sequence data is outlined by G. M. Garrity and J. G. Holt (2001) in Bergey’s
Manual of Systematic Bacteriology, 2nd Edition, Volume 1, Garrity, G. M. (ed.), pp. 119–123, New York: Springer-Verlag. (Courtesy
of Peter H. A. Sneath.)

FIGURE 01-07: Occurrence of major phenotypic groups within the 25 prokaryotic phyla. This figure illustrates the relationship
between these phyla and the major phenotypic groups of prokaryotes selected as the basis of the classification in the earlier version of
Bergey’s Manual of Systematic Bacteriology (ninth edition). [Reproduced with permission from Garrity, G.M., and Holt, J.G. (2001),
The road map to the manual. In Bergey’s Manual of Systematic Bacteriology, 2nd Edition, Volume 1, Garrity, G.M. (ed.) p. 124, New
York: Springer-Verlag.]

FIGURE 01-08: Diagrammatic representation of lateral gene transfer and recombination events leading to the incorporation
of a short segment of the 16S rRNA gene of Mesorhizobium mediterraneum (Upm-Ca 36) into the 16S rRNA gene of
Bradyrhizobium elkanii to produce the present day B. elkanii (USDA 76) 16S rRNA gene. [Based on data from van Berkum,
P., et al. (2003). Discordant phylogenies within the rrn loci of Rhizobia. Journal of Bacteriology, 185, 2988–2998.]

FIGURE 01-09: Temperature dependence of the absorbance of a
solution of a perfectly complementary DNA hybrid duplex at 260
nm (A260). The separation of the two strands (also termed the
“melting” of the DNA) is accompanied by an increase in the
absorbance at 260 nm. The temperature at which the change in
A260 is 50% complete is designated as the melting temperature
(Tm). The Tm is sensitive to the pH and ionic strength of the
buffer. In the representation of a heterologous hybrid (upper
diagram), the arrows point to noncomplementary positions in the
two DNA sequences. Such a hybrid would have a much lower
Tm than the perfectly Complementary hybrid duplex whose
melting curve is shown here.

FIGURE 01-10: Hybridization of oligonucleotide probes
to a target DNA sequence. The sequence of probe 1 is
perfectly complementary to that of the target DNA,
whereas there is one mismatch (position indicated in
boldface in the sequence of the target DNA) in each of
the
oligonucleotide probes 2 and 3. The black
dot at the 5 end of each probe indicates a covalently
attached fluorescent label. The lower panel illustrates the
dissociation profile of each of the hybrids. Note that the
higher the Tm the higher the stringency of hybridization.

FIGURE 01-11: Cells captured from environmental samples were encapsulated into gel microdroplets (GMDs) and
incubated in growth columns (phase I). GMDs containing colonies were detected and separated by flow cytometry into 96-
well microtiter plates containing a rich organic medium (phase II). [Reproduced with permission from Zengler, K., Toledo,
G., Rappe, M., Elkins, J., Mathur, E. J., Short, J. M., and Keller, M. (2002). Cultivating the uncultivated. Proceedings of the
National Academy of Sciences U.S.A., 99, 15681–15686.]

FIGURE 01-12: Discrimination among (A) free-living cells, (B) singly occupied or empty GMDs, and (C) GMDs containing
microcolonies was accomplished by flow cytometry in forward and side light-scatter mode. (D, E, and F) Phase contrast photomicrographs
of separated GMDs containing microcolonies. Bar = 50 μm. [Reproduced with permission from Zengler, K., Toledo, G., Rappe, M.,
Elkins, J.,Mathur, E. J., Short, J. M., and Keller, M. (2002). Cultivating the uncultivated. Proceedings of the National Academy of Sciences
U.S.A., 99, 15681–15686.]

FIGURE 01-13: Gluconic acid.

FIGURE 11-14: (A) The reproduction of yeast is normally
asexual, proceeding by the formation of buds on the cell surface,
but sexual reproduction can be induced under special conditions.
In the sexual cycle, a normal diploid cell by meiosis and
sporulation gives rise to asci, or spore cells, that contain four
haploid ascospores. The ascospores are of two mating types: a
and α. Each type can develop by budding into other haploid
cells. The mating of an a haploid cell and an α haploid cell yields
a normal a/α diploid cell. Haploid cells of the same sex can also
unite occasionally to form abnormal diploid cells (a/a or α/α)
that can reproduce only asexually, by budding in the usual way.
The majority of industrial yeasts reproduce by budding. (B)
Reproduction of a multicellular fungus, such as one of the higher
ascomycetes, can be asexual or sexual. The details vary with
genus and species. The branched vegetative structure common to
both reproductive cycles is the mycelium, composed of hyphae
(1). In the asexual cycle, the mycelium gives rise to
conidiophores that bear the spores called conidia, which are
dispersed by the wind. In the sexual cycle, the mycelium
develops gametangial structures (2), each consisting of an
antheridium (containing “+” nuclei) and an ascogonium
(containing “−” nuclei). The nuclei pair in the ascogonium but do
not fuse. Ascogenous binucleate hyphae develop from the
fertilized ascogonium (3), and the pairs of nuclei undergo
mitosis, which replicates the newly paired chromosomes. Finally,
some pairs of nuclei fuse, a process called karyogamy (4), at the
tips of the ascogenous hyphae. This is the only diploid stage in
the life cycle. Soon afterward, the diploid nuclei (large dots)
undergo meiosis, or reduction division. The result is eight
haploid nuclei (small dots), each of which develops into an
ascospore. At the same time, the developing asci are enclosed by
mycelial hyphae in an ascocarp (5). In the example shown here,
the ascocarp is a cleistothecium, a closed structure. Ascospores
germinate to yield binucleate or multinucleate
mycelium (6). [After Phaff, H. (1981). Industrial
microorganisms. Scientific American, 245, 76–89.]

FIGURE 01-15: Aflatoxin B1.