Concept explainers
Bacteria are prokaryotic microorganism. They can grow and live in various environments like soil, ocean, inside rocks and animals. Some bacteria are involved in symbiotic relationships and others may cause serious health problems to humans and animals. Gram-negative bacteria use secretion systems (types I to VI) to insert substances or effector molecules (proteins, toxins, or enzymes) into their outer membranes or secrete substances outside of the gram-negative bacterial cell. Type I to VI secretion systems in gram-negative bacteria facilitate various biological activities such as symbiotic interactions, extracellular enzyme secretion, biofilm formation, release of antibiotics, DNA transfer, and transfer of protein molecules into host cells. Secreted substances by secretion systems help the interaction of bacterial with other organisms or their environment.
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Brock Biology of Microorganisms (15th Edition)
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- What are the short DNA sequences that are near a desired gene? What combines with other proteins to form an organelle responsible for protein synthesis?arrow_forwardWhat is a nucleosome-free region? Where are such regions typically found in a genome? How are nucleosome-free regions thought to be functionally important?arrow_forwardIn a study showing that approximately 10% of protein-coding genes are essential for Cell survival .This translates into which of the following number of essential genes in the human genome .a)100 b) 500 c)1000 d)2000arrow_forward
- A mutation creates a dominant negative allele of a particular gene. The gene encodes a protein that forms a trimer within the cell. If one or more of the subunits has the mutant structure, the entire trimeric protein is inactive. In a heterozygous cell, if the proteins of both alleles are present at the same levels, what percent of the trimers present in the cell will be active? A) 100% B) 5% C) 50% D) 33% E) 5%arrow_forwardWhat is the substrate of a histone acetyltransferase? A) transcription B) transferase C) histone D) DNA E) ribosome F) not enough information to tellarrow_forwardHow many copies of each type of core histone would it take to wrap the entire human genome into nucleosomes? How has evolution solved the problem of producing such a large number of proteins in a relatively short period of time?arrow_forward
- Principles Of Radiographic Imaging: An Art And A ...Health & NutritionISBN:9781337711067Author:Richard R. Carlton, Arlene M. Adler, Vesna BalacPublisher:Cengage Learning