plant surface microbiology.pdf

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Galdino Andrade
and 2–15 % protein. Soluble substances, such as sugars, amino sugars, organic
acids, and amino acids, can constitute 10 % of the dry weight (Paul and Clark
1989). Soil microbes use residue components as substrates for energy and also
as carbon sources in the synthesis of new cells. The presence or absence of
substrates can increase or decrease the populations.
Microorganism populations capable of cellulose, starch and both animal
and plant protein hydrolisation can be assessed in the carbon cycle. These
polymers are broken into smaller units of sugars and amino acids, respectively
(Fig. 3).
The functional group of cellulotic microorganisms is formed by fungi,
actinomycetes and bacteria. These microorganisms can produce exoenzymes
called cellulases. The term cellulase describes a diversity of enzyme complexes
that act in two distinct stages. First, there is a loss of the crystalline
Photosynthesis
POLYMERS
Celulose, Starch, Protein
Hidrolytic
Activity
UNITS
Sugar, Amino acids
Aerobic
Microorganisms
Plant
Biosynthesis
Sun Light
CO2
CO2 + H2O
Energy
Biomass
Fig. 3. The activity of some functional groups of
microorganisms in the carbon cycle