A Study On The Lac Operon - 1332 Words

Charisse Young Bio 121 Section PR 12/7/14 Question #1. The lac operon is a clustered group of related genes that are transcribed as a single unit. These genes produce the enzymes to break down the sugar lactose in prokaryotes. Trp operon also in E. coli contains genes that codes for enzymes that produce tryptophan. Both the lac operon and the trp operon can act negatively and positively in controlling transcription. The lac operon is regulated by a repressor protein that blocks transcription from occurring. The trp operon is regulated by the trp repressor protein that binds to the operator and blocks transcription. Positive control that stimulates transcription is done by the protein activators. This positive control increases the frequency of the production of more proteins and more enzymes which equals more gene expression. The repressor proteins produces less proteins, less enzymes and equals less gene expression. Question #2. Proteins interact with DNA through the major groove. Scientist have discovered that it is unnecessary for the helix to unwind for proteins to distinguish one DNA sequence from the other. The major groove of the double helix is where proteins bind to interact with the base pairs. The major groove is defined as the larger of the two grooves in a DNA helix, where the paired nucleotides’ hydrogen bonds are accessible. DNA-binding motifs are three-dimensional structures that are found in proteins. These motifs are inserted into theShow MoreRelatedChapter 13 Review9122 Words   |  37 Pagesof mammalian development. false 3 RNA polymerase can bind to the promoter region of the DNA even when the lac repressor is bound to the operator site. true Hide 4 Both eukaryotes and prokaryotes require a promoter region for gene transcription. true 5 Eukaryotic genes are almost always organized in groups, similar to operons in prokaryotes. false Advertisement Hide ads ($1). 6 Unmethylated CpG islands are correlated with inactiveRead MoreBiology : Evolution, Energy, Information, And Systems1436 Words   |  6 PagesBiology, the study of life and living organisms, is complex and encompasses a multitude of theories and ideas. In AP Biology, the fourth unit covered was genetics. Chapters 11, 12, 13, 14, 15, 16, and 18 in the textbook, Campbell’s Biology in Focus, not only discusses the four main ideas of biology: evolution, energy, information, and systems, but it also gives examples of each in order to help guide the reader’s understanding of the concepts. The first big idea of AP Biology is: â€Å"the processRead MoreSalmonella Bacteria For Producing Protein Of Interest And Rate Growth And Protein Concentration After Inoculate The E.coli Culture1137 Words   |  5 Pageshigher cost, difficult optimization of media, and very low yield of the desire protein [4,8 and 10]. In bacteria, such as E. coli, operon codes include the expression of three separate enzymes needed for lactose metabolism. Prior to the operon a regulatory gene continually makes repressor proteins that bind with the operator thus restrain the transcription of the operon. Indeed, the system remains off until lactose molecules bind to the repressors and prevents their attachment to the operator. OnceRead MoreCauses Of Biofilm Formation1317 Words   |  6 Pages The primary investigators of the research study include Sana S. Dastgheyb, Amer E. Villaruz, Katherine Y. Le, Vee Y. Tan, Anthony C. Duong, Som S. Chatterjee, Gordon Y. C. Cheung, Hwang-Soo Joo, Noreen J. Hickok and Michael Otto. The locations at which the studies were conducted include the institutions that each author is associated with. Those include the National Institute of Allergy and Infectious Diseases at Bethesda, Maryland and the Thomas Jefferson University located in PhiladelphiaRead MoreScientific Article Analysis1739 Words   |  7 Pagesinterest to this scientific investigation is the wide spread antibiotic resistance of S. aureus; infections subsequent to joint reconstructions and replacements can lead to amputations, systemic infections, and death. The authors of the present study recently showed that the extreme resistance of S. aureus to antibiotics reflects pronounced biofilm formation and bacterial agglomeration. Presumbably, the antibiotic cannot reach its potential target. As these agglomerates of cells increase in sizeRead MoreSynovial Bacterial Lab1770 Words   |  8 Pagesof PSMs; l. Statistics. C. What are the general results/conclusions from the study? a. Their findings suggest that therapeutic strategies against staphylococcal PJI should target the host-derived and bacterial factors that contribute to agglomerate, such as fibrin and bacterial biofilm matrix molecules, including PIA. INTRODUCTION 3. A. Describe any important background research/information important to the study. a. 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As proteins are involve in important life processes so production of these proteins is very important at industrial level. Proteins have been studied and analysed in their purified form. Many molecular techniques have been used to study proteins t o know their structure and function. The function of proteins is described by the structure. The three-dimensionalRead MoreThe Use Of Bacteria For Recombinant Protein Production1283 Words   |  6 Pagesapplied with UV light. In the arabinose gene expression operon, genes are controlled by the use of plasmid cloning vectors ara (arabinose) promoter and the lac (lactose) structural genes, which were created for the recognition and analysis of signals which are responsible for gene transcription. Expression of the lac genes in the absence of the inducer arabinose indicates that transcription originates within the inserted fragment; non-expression of lac with arabinose present indicates that transcriptionRead MorePhenol-Soluble Modelins In Synovial Flu-Sb Case Study1261 Words   |  6 Pagessurface attached proteins such as fibrin which is available in the infected joint due to its role recovery of injured tissues. They found that bacteria mutants that cannot utilize fibrinogen were unable to form the macroscopic complexes. In this study, they focused on finding a mechanistic way that S. aureus forms these ex-tremely large biofilms in synovial fluid by testing altered expressions of specific bacterial factors. They also tested the Agr gene and PSM’s roles in formation of biofilms.