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Molecule Parameter List for RNAP

The statistics table lists the distribution of a molecule acting either as a substrate, product, enzyme or as a molecule within the network.
The text color of a molecule is highlighted by color.
Statistics
RNAP participated asMoleculeSum total ofEnzymeSubstrate of an enzymeProduct of an enzymeSubstrate in ReactionProduct in Reaction
No. of occurrences1000011

Accession and Pathway Details
Accession NameAccession No.Accession TypePathway Link
Kierzek_LacZ29Pathway
LacZ 
An approximation to the Kierzek AM. et al. J Biol Chem. (2001) 276(11):8165-72 model of LacZ gene expression in E. coli. They use stochastic simulation and model cell growth. Despite these discrepancies, the continuous fixed size model is within a factor of 3 of their results. Parameter values are identical.

RNAP acting as a Molecule in  
Kierzek_LacZ Network
NameAccession NamePathway NameInitial Conc.
(uM)
Volume
(fL)
Buffered
RNAPKierzek_LacZ
Accession No. : 29
LacZ
Pathway No. : 141
0.05830.99997Yes
RNA Polymerase. Kierzek et al assume mean 35 and delta = 3.5 molecules. Turns out they assume that this is buffered.

RNAP acting as a Substrate in a reaction in  
Kierzek_LacZ Network
Kd is calculated only for second order reactions, like nA+nB <->nC or nA<->nC+nD, where n is number and A,B,C,D are molecules, where as for first order reactions Keq is calculated. Kd for higher order reaction are not consider.
NameAccession NamePathway NameKfKbKdtauReagents
RNAPol_bindingKierzek_LacZ
Accession No. : 29
LacZ
Pathway No. : 141
99.9927
(uM^-1 s^-1)
10
(s^-1)
Kd(bf) = 0.1(uM)-Substrate
P
RNAP

Product
P_RNAP
Equations 1 and 2 from Kierzek et al. Reversible RNA polymerase binding.

RNAP acting as a Product in a reaction in  
Kierzek_LacZ Network
Kd is calculated only for second order reactions, like nA+nB <->nC or nA<->nC+nD, where n is number and A,B,C,D are molecules, where as for first order reactions Keq is calculated. Kd for higher order reaction are not consider.
NameAccession NamePathway NameKfKbKdtauReagents
RNASynthesisKierzek_LacZ
Accession No. : 29
LacZ
Pathway No. : 141
1
(s^-1)
0
(uM^-3 s^-1)
--Substrate
TrRNAP

Product
ElRNAP
P
RBS
RNAP
Equation 4 from Kierzek et al. They say: To clear the promoter region, active RNA polymerase must move 30 to 60 nucleotides (ref Record et al 1996 E coli and Salmonella 2nd ed pp 792-821 ASM Press, Washington DC) Since rate of polymerase movement is about 40 nucleotides/sec, this step takes about 1 sec. The length of the mRNA chain that is synthesized during this time corresponds roughly to the length of the leader region containing the ribosome binding site (RBS). Therefore the synthesis of the RBS and promotor clearance occur at approximately the same rate of 1 per sec. .... Therefore we modeled these two processes by the single first order reaction with a rate constant of 1 per sec.



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