Effects of pH strategy on endo- and exo-metabolome profiles and sodium potassium hydrogen ports of beta-lactamase-producing Bacillus licheniformis

2006-03-01
Ileri, N
Çalık, Pınar
The effects of pH strategy on endo- and exo-metabolome profiling of beta-lactamase-producing Bacillus licheniformis were investigated at controlled-pH (pH(C) = 6.5, 6.75, 7.0, 7.25, 7.5) and uncontrolled-pH (pH(UC) = 7.5) values using a glucose-based defined medium. The cell concentration profiles were not affected by the pH considerably within the investigated range. The highest enzyme activities were obtained as A = 54 U cm(-3) at pHc = 6.75 among the controlled-pH operations and as A = 57 U cm(-3) at the uncontrolled-pH pH(UC) = 7.5. At all conditions, oxygen transfer resistances were more effective, whereas the limitation increased in the beta-lactamase production phase. Total intracellular an-Lino acid concentrations ranged between 0.142 and 6.766 kg m(-3) (0.0058-0.277 g g(cell)(-1)), and their concentrations in terms of kg m(-3) were, at most, 580-fold higher than the extracellular concentrations. Methionine/cysteine concentrations were generally higher than the other intracellular amino acids, whereas asparagine concentration was the highest in the fermentation broth. From Na+, K+, and H+ ion profiles, Na+-K+ antiport and Na+-H+ symport were found to be present within the system, and a correlation was found between organic acid transport and Na+-H+ symport. intracellular organic acid concentrations in terms of kg m(-3) were, at most, 20-fold higher than that of the extracellular, and with the increase in pH, extracellular acetic acid concentration increased and lactic acid concentration decreased. Average permeability coefficient values of organic acids were found to be in the range from 4.10 x 10(-7) to 4.32 x 10(-6) cm s(-1) for the growth phase (0 < t < 6 h) and decreased at least 3-fold in the beta-lactamase production phase (8 < t < 15 h), indicating the considerable structural change of the lipid membrane during the fermentation.
BIOTECHNOLOGY PROGRESS

Suggestions

Effects of pH and feeding strategy on metabolite profiling of beta-lactamase producing bacillus licheniformis
İler, Nazar; Çalık, Pınar; Department of Chemical Engineering (2005)
In this study, the effects of pH and different feeding modes on beta-lactamase production and cell metabolism were investigated with Bacillus licheniformis (ATCC 25972). For this purpose, first, the effects of pH on beta-lactamase activity, cell formation, substrate consumption, as well as intracellular sodium, potassium, ammonium ion, amino acid and organic acid concentrations were investigated in V= 3.0 dm3 batch bioreactors consisting of temperature, pH, foam, stirring rate and dissolved oxygen controls....
Influence of oxygen transfer on benzaldehyde lyase production by recombinant Escherichia coli BL21(DE3) pLySs
Angardi, Vahideh; Çalık, Pınar; Department of Chemical Engineering (2007)
In this study, the effects of oxygen transfer conditions on the synthesis of the enzyme benzaldehyde lyase as intracellular in recombinant E. coli BL21 (DE3) pLysS was investigated sistematically and a comprehensive model was developed to determine benzaldehyde lyase activity. For this purpose, the research program was carried out in mainly two parts. In the first part of study, the effects of oxygen transfer together with the mass transfer coefficient (KLa), enhancement factor E (=KLa/KLao), volumetric oxy...
Effects of pulse feeding of beet molasses on recombinant benzaldehyde lyase production by Escherichia coli BL21(DE3)
Çalık, Pınar (Springer Science and Business Media LLC, 2009-11-01)
The effect of fed-batch operation (FBO) strategy was investigated using pretreated-beet molasses, containing galactose that induces the lac promoter, on benzaldehyde lyase (BAL) production by recombinant Escherichia coli BL21(DE3)pLySs. After batch cultivation with 30 g l(-1) pretreated-beet molasses consisting of 7.5 g l(-1) glucose and 7.5 g l(-1) fructose, three FBO strategies were applied at dissolved oxygen (=40%) cascade to air-flow rate. In FBO1 when air-flow rate decreased considerably, feed was giv...
Effects of antimitotic agents on haploid plant production from unpollinated ovules of sugar beet (beta vulgaris l.)
Gürel, S.; Gürel, E.; Kaya, Zeki; Erdal, M.; Güler, E. (Informa UK Limited, 2003-01-01)
The effects of antimicrotubule agents on haploid embryo formation from unpollinated ovules of sugar beet (Beta vulgaris L.) were investigated. The antimitotic agent colchicine (at 100 and 150 mg/l) and trifluralin (at 5.0 mg/l) increased the frequency of haploid embryo formation whereas pronamide (at 76.9 and 128.2 mg/l) and trifluralin (at 3.4 mg/l) decreased. Ovules that were non-treated with antimicrotuble agents (i.e., ovules of the control treatment) produced higher percentages of haploid embryos (4.25...
Molecular cloning and co-expression of Thermoplasma volcanium proteasome subunit genes
Kocabıyık, Semra; Zwickl, Peter; Ozdogan, Seda (Elsevier BV, 2010-10-01)
In this study we describe, the construction of a co-expression vector allowing simultaneous production of Thermoplasma volcanium 20S proteasome alpha- and beta-subunits in Escherichia coli. This heterologous expression system provided high level production of fully active 205 proteasome that can be purified easily by using a conventional two-step chromatographic technique. The recombinant proteasome was purified to homogeneity 12-fold with a specific activity of 26.5 U/mg. Sodium dodecyl sulfate-polyacrylam...
Citation Formats
N. Ileri and P. Çalık, “Effects of pH strategy on endo- and exo-metabolome profiles and sodium potassium hydrogen ports of beta-lactamase-producing Bacillus licheniformis,” BIOTECHNOLOGY PROGRESS, pp. 411–419, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46087.