Nitrogen limitations

Figure 3.2 Theoretical relationships for (a) qs against dilution rate and for (b) Yp/S and Yx/s against dilution rate. The micro-organism is grown aerobically in a nitrogen limited chemostat culture.

Table 3.3 Experimental stoichiometries for cell growth and exopolysaccharide production from various carbon sources by Agrvbacterhim radlobacter under nitrogen-limiting conditions.

The requirement for oxygen and carbon source for cell biosynthesis are calculated using nitrogen-limited mass balance equations for growth during exopolysaccharide production 01 res (nitrogen-limited cultures). These balances are derived from experimentally determined values of ... 

An issue of particular relevance in the context of bioremediation is illustrated by the increased rate of cell death in an established naphthalene-degrading Pseudomonas putida G7 brought about by the substrate (naphthalene) under conditions of oxygen (or combined oxygen and nitrogen) limitation (Ahn et al. 1998). 

Expression of lignin peroxidases in Phanerochaete chtysosporium is induced by nitrogen-limitation, and by the concentration of Mn (11) in the medium (Perez and Jeffries 1990). 

The degradation of chlorinated phenols has been examined with the white-rot basidiomy-cete Phanerochaete chrysosporium under conditions of nitrogen limitation, and apparently involves both lignin peroxidase and manganese-dependent peroxidase activities (Valli and Gold 1991). 

If oxygen limits growth and multiplication of aerobic bacteria, the adaptive value and inductive mechanism of poly(3HB) synthesis are quite similar to those outlined for nitrogen limitation. 2/H/ generated are not oxidized via elec-... 

Howarth, R.W. and J.J. Cole. 1985. Molybdenum availability, nitrogen limitation, and phytoplankton growth in natural waters. Science 229 653-655. 

K. Miyamoto PC. Hallenbeck, JR. Benemann (1979) Solar energy conversion by nitrogen-limited cultures of Anabaena cylindrica. J. Ferment. Technol., 57 287-293... 

Anabaena cylindrica sp. PCC7I20 [NiFe] hydrogenase Putative membrane- bound cytochrome b reducing H2 recycling during N2 fixation O2, nitrogen limitation, heterocyst formation 2... 

This process is commonly referred to as assimilatory nitrogen (nitrate or nitrite) reduction. The electrons for these reductions are supplied by half-cell oxidations involving NADPH/NADP" and NADH/NAD" (Table 7.11). All of these reactions and membrane transport processes are mediated by enzymes that are specific to the DIN species. Considerable variation exists among the phytoplankton species in their ability to produce the necessary enzymes. Since marine phytoplankton are often nitrogen limited, the quantity and type of DIN available in the water column can greatly influence overall phytoplankton abundance and species diversity. 

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