Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Growth and kappa-carrageenan immobilization of Pseudomonas dacunhae cells for L-alanine production
Date
1999-01-01
Author
Çalık, Pınar
Ozdamar, TH
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
182
views
0
downloads
Cite This
Industrial production of L-alanine is accomplished from L-aspartic acid using L-aspartate beta-decarboxylase (ADL) enzyme of resting Pseudomonas dacunhae cells as the biocatalyst. This work reports on the effect of inoculation ratio, agitation rate, and pH control on the cell concentration and enzyme activity during the growth as well as the effects of different kappa-carrageenan-immobilization procedures applied to the active cells and the kinetics of the biocatalyst pellets. Although the cell concentration was not affected lower inoculation ratios increased the activity of the produced enzyme. Both the cell concentration and the ADL activity increased with the agitation rate. The activity and the stability of the biocatalyst pellets were retained more when the immobilized cells were treated with the cross-linking agents hexamethylenediamine (HMDA) and glutaraldehyde (GA). Pellet size and agitation rate investigations showed that intraphase mass transfer limitations are present. An increase in the pellet concentration increased the initial reaction rate but its effect was not very significant after 100 kg m(-3) Optimum initial pH range far the L-alanine production reaction for the free and HMDA + GA-treated immobilized cells (P-8 pellets) were 6.0-6.2. Optimum temperature was 323 K and 333 K for the free cells and the P-8 pellets, respectively. Substrate activation mechanism was valid for the L-alanine production with the free cells while for the P-8 pellets Michealis-Menten mechanism was satisfactory. (C) 1998 Elsevier Science Inc.
Subject Keywords
Biotechnology
,
Applied Microbiology and Biotechnology
,
Biochemistry
URI
https://hdl.handle.net/11511/43360
Journal
ENZYME AND MICROBIAL TECHNOLOGY
DOI
https://doi.org/10.1016/s0141-0229(98)00091-x
Collections
Department of Chemical Engineering, Article
Suggestions
OpenMETU
Core
Overexpression of serine alkaline protease encoding gene in Bacillus species: performance analyses
Çalık, Pınar; Ozdamar, TH (Elsevier BV, 2003-12-02)
Bacillus species carrying subC gene encoding serine alkaline protease (SAP) enzyme were developed in order to increase the yield and selectivity in the bioprocess for SAP production. For this aim, subC gene was cloned into pHV1431 Escherichia coli-Bacillus shuttle vector, and transferred into nine host Bacillus species, i.e. B. alvei, B. amyloliquefaciens, B. badius, B. cereus, B. coagulans, B. firmus, B. licheniformis, B. sphaericus and B. subtilis. The influence of the host Bacillus species on SAP product...
SURVIVAL KINETICS OF LACTIC-ACID STARTER CULTURES DURING AND AFTER FREEZE-DRYING
BOZOGLU, F; OZILGEN, M; BAKIR, U (Elsevier BV, 1987-09-01)
Survival kinetics of lactic acid starter cultures were modeled considering the microorganism and external medium interfacial area as the critical factors determining the resistance of the microorganisms to freeze-drying. Surviving fraction of the microorganisms increased with the increasing biomass concentration during freeze-drying, and this is attributed to the mutual shielding effect of the microorganisms against the severe conditions of the external medium. Survival of the microorganisms over the storag...
Mass flux balance-based model and metabolic pathway engineering analysis for serine alkaline protease synthesis by Bacillus licheniformis
Çalık, Pınar (Elsevier BV, 1999-07-01)
A mass flux balance-based stoichiometric model of Bacillus licheniformis for the serine alkaline protease (SAP) fermentation process has been established. The model considers 147 reaction fluxes, and there are 105 metabolites that are assumed to be in pseudo-steady state. Metabolic flux distributions were obtained from the solution of the model based on the minimum SAP accumulation rate assumption in B. licheniformis in combination with the off-line extracellular analyses of the metabolites that were the so...
Protein-based complex medium design for recombinant serine alkaline protease production
Çalık, Pınar; Telli, IE; Oktar, C; Ozdemir, E (Elsevier BV, 2003-12-02)
This work reports on the design of a complex medium based on simple and complex carbon sources, i.e. glucose, sucrose, molasses, and defatted-soybean, and simple and complex nitrogen sources, i.e. (NH4)(2)HPO4, casein, and defatted-soybean, for serine alkaline protease (SAP) production by recombinant Bacillus subtilis carrying pHV1431::subC gene. SAP activity was obtained as 3050 U cm(-3) with the initial defatted-soybean concentration C-soybean(o) = 20 kg m(-3) and initial glucose concentration C-G(o) = 8 ...
Analysis of acyl CoA ester intermediates of the mevalonate pathway in Saccharomyces cerevisiae.
Şeker, Tamay; Nielsen, J (Springer Science and Business Media LLC, 2005-04-01)
The mevalonate pathway plays an important role in providing the cell with a number of essential precursors for the synthesis of biomass constituents. With respect to their chemical structure, the metabolites of this pathway can be divided into two groups: acyl esters [acetoacetyl CoA, acetyl CoA, hydroxymethylglutaryl (HMG) CoA] and phosphorylated metabolites (isopentenyl pyrophosphate, dimethylallyl pyrophosphate, geranyl pyrophosphate, farnesyl pyrophosphate). In this study, we developed a method for the ...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
P. Çalık and T. Ozdamar, “Growth and kappa-carrageenan immobilization of Pseudomonas dacunhae cells for L-alanine production,”
ENZYME AND MICROBIAL TECHNOLOGY
, pp. 67–74, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43360.