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... In mammals, some tissues depend almost completely on glucose for their metabolic energy. Glucose from the blood is the sole or major fuel source for: • Human brain and nervous system - Brain requires 120 g/day, more than half that is stored as glycogen in muscles and liver. ...
Lehninger Principles of Biochemistry
Lehninger Principles of Biochemistry

... Glucagon, a pancreatic hormone, signals low blood sugar and lowers the level of fructose 2,6-bisphosphate in the liver. This stimulates gluconeogenesis and the production of glucose. ...
Chapter 27 Reproductive Endocrinology
Chapter 27 Reproductive Endocrinology

... bone, teeth, DNA, RNA, ATP ...
The serC-aroA operon of Escherichia coli
The serC-aroA operon of Escherichia coli

... into pAT153. aroA recombinant plasmids were isolated and characterized as described in Duncan et al. (1984a) (Fig. 1). These constructions (pKD503, pKD504 and pKD505) placed the boundary of the aroA gene between the ClaI site and the PstI site on the phage. A 1.9 kb ClaI-PvuII fragment from pKD501 w ...
Transcription
Transcription

... of sequences with a two-fold symmetry that makes a hairpin loop, followed by 4-8 AT basepairs, leading to termination when encountered. – Rho-dependent termination. These sequences lack AT string and many cannot form hairpin structures. Rho factor (a protein) is needed to recognize a specific sequen ...
Figure 17-3 Degradation of glucose via the glycolytic pathway.
Figure 17-3 Degradation of glucose via the glycolytic pathway.

... Gluconeogenesis 1. What is the role of this pathway? Convert 3-C lactate or pyruvate into 6-C glucose 2. What is the difference between glycolysis and gluconeogenesis? Need to by-pass the three irreversible steps 3. Where is the pathway located? Uses enzymes located in the cytosol and mito ...
Friesland Foods Normal
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... are presented in Tables 1 and 2 and given in supplementary file 1. Remarkably, the set of genes (and corresponding proteins) can be divided into five separate groups on basis of genomic organisation, the identity of the EC numbers and the position in the reaction network (see Figure 1). Small diffe ...
New Insight into the Main Metabolic Regulation of Escherichia Coli
New Insight into the Main Metabolic Regulation of Escherichia Coli

... Note that although the TCA cycle activity may be repressed based on gene expression data, the specific glucose consumption rate increases, and thus the absolute TCA cycle fluxes tends to increase on the mmol basis by taking into account the specific glucose consumption rate (Yao et al., 2011). This ...
Glycolysis and Gluconeogenesis
Glycolysis and Gluconeogenesis

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gen-305-presentation-13-2016
gen-305-presentation-13-2016

... As an mRNA ages, its polyA tail is shortened by the action of cellular nucleases The polyA-binding protein can no longer bind if the polyA tail is less than 10 to 30 adenosines long  The mRNA will then be rapidly degraded by exo- and ...
BHS 150.1 – Biochemistry II Date: 2/1/2013, 2sndhalf Notetaker: Kim
BHS 150.1 – Biochemistry II Date: 2/1/2013, 2sndhalf Notetaker: Kim

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Artifact 1
Artifact 1

... split the six carbon chain into dihydroxyacetone phosphate and glyceraldehyde. A  deficiency of aldolase B is a more serious genetic defect that results in an accumulation  of fructose‐1‐phosphate, and trapping of phosphate. Aldolase B is essential in  carbohydrate metabolism as it catalyzes this ma ...
When muscular work starts, the adrenal medulla secretes a
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... This ends the preparatory phase of glycolysis. Two molecules of ATP must be invested to activate or prime the glucose molecule for its cleavage into two three carbon pieces; later there will be a good return on this investment. The energy gain comes in the payoff phase of glycolysis. Each molecule o ...
Document
Document

... Enters glycolysis by two different pathways depending on the tissue. Skeletal muscles The glycolytic enzyme, hexokinase accepts fructose as a substrate but with only 5% of the affinity of glucose. ...
Chapter 16 Glycolysis and gluconeogenesis
Chapter 16 Glycolysis and gluconeogenesis

... for the formation of fatty acid its affinity for glucose is about 50-fold lower than that of hexokinase  brain and muscle first call on glucose when its supply is limited. P. 456 ...
Lecture 7: Metabolic Regulation - University of California, Berkeley
Lecture 7: Metabolic Regulation - University of California, Berkeley

... Amplification. You do this in many steps to amplify the effect. You come in with one signal molecule of epinephrine, which will activate the receptor. The receptor will activate many G-proteins. Each of these Gproteins will activate adenylylate cyclase. cAMP will activate many PKA enzymes. At every ...
Lecture_5_Control_of_glycolysis
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... Pyruvate carboxylase functions as a tetramer composed of four identical subunits, and each subunit consists of four domains. The biotin carboxylase domain (BC) catalyzes the formation of carboxyphosphate and the subsequent attachment of CO2 to the second domain, the biotin carboxyl carrier protein ...
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... Types of Diabetes ------ Historical development of nomenclature 5. Pathologic states associated with diabetes CAD Peripheral neuropathy PAD Distal limb amputations CRF Retinopathy Cataracts 6. Underlying mechanisms: Glycosylation of proteins (Fig. 9-5 (Metab)) ----- membrane dysfunction Polyol forma ...
Dysglycemia refers to any disorders in serum (blood) glucose
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... between lypolysis and lipogenesis, decrease the activity and synthesis of thyroid hormones, upregulate the immune system and many other stressful and destructive effects. Infections will uncouple the citric acid cycle by disturbing phosphorylation. Gastro intestinal dysfunction may induce anemia, th ...
12918_2009_420_moesm5_esm - Springer Static Content Server
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... biomass, we followed well established procedures. Where possible, data specific to C. thermocellum was used, but where necessary we used information specific for the gram positive microorganism Bacillus subtilis, for which there already exists a genome scale metabolic model (Oh et al 2007). All calc ...
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ch18 - Homework Market

... • Inducer inactivates the repressor  turns on transcription • Ex: lac operon ...
bme-biochem-5-1-atp-adp-cycle-kh-6
bme-biochem-5-1-atp-adp-cycle-kh-6

... Glycogenesis: The process by which glycogen is synthesized from glucose; in which glucose molecules are added to chains of glycogen for storage. Glycogenolysis: (also known as "Glycogenlysis") is the break down of glycogen to glucose-1-phosphate and glucose for ATP production. Gluconeogenesis (abbre ...


... B15 (13 pts) The HIV reverse transcriptase (HIV-RT) is also a drug target for AIDS drugs. As with the HIV protease, mutations arise in this enzyme, generating HIV viruses that are resistant to existing drugs. Pharmaceutical companies would like to characterize these altered reverse transcriptases to ...
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Pyruvate Glucose - School of Medicine

... • Fructose 1,6-bisphosphatase is an allosteric enzyme and regulates ...
Genes required for Lactococcus garvieae survival in a fish host
Genes required for Lactococcus garvieae survival in a fish host

... (STM). STM relies on two key elements. First, a negative selection will select against replication of mutant strains where a transposon-mediated disruption of genes related to virulence has occurred. Second, as each mutagenizing transposon carries ‘signature tags’ (DNA fragments consisting of a cent ...
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Lac operon



lac operon (lactose operon) is an operon required for the transport and metabolism of lactose in Escherichia coli and many other enteric bacteria. Although glucose is the preferred carbon source for most bacteria, the lac operon allows for the effective digestion of lactose when glucose is not available. Gene regulation of the lac operon was the first genetic regulatory mechanism to be understood clearly, so it has become a foremost example of prokaryotic gene regulation. It is often discussed in introductory molecular and cellular biology classes at universities for this reason.Bacterial operons are polycistronic transcripts that are able to produce multiple proteins from one mRNA transcript. In this case, when lactose is required as a sugar source for the bacterium, the three genes of the lac operon can be expressed and their subsequent proteins translated: lacZ, lacY, and lacA. The gene product of lacZ is β-galactosidase which cleaves lactose, a disaccharide, into glucose and galactose. LacY encodes lactose permease, a protein which becomes embedded in the cytoplasmic membrane to enable transport of lactose into the cell. Finally, lacA encodes galactoside O-acetyltransferase. Layout of the lac operon.It would be wasteful to produce the enzymes when there is no lactose available or if there is a more preferable energy source available, such as glucose. The lac operon uses a two-part control mechanism to ensure that the cell expends energy producing the enzymes encoded by the lac operon only when necessary. In the absence of lactose, the lac repressor halts production of the enzymes encoded by the lac operon. In the presence of glucose, the catabolite activator protein (CAP), required for production of the enzymes, remains inactive, and EIIAGlc shuts down lactose permease to prevent transport of lactose into the cell. This dual control mechanism causes the sequential utilization of glucose and lactose in two distinct growth phases, known as diauxie.
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