Chromosome encoding

Figure 9-27. An artificial chromosome, encoded as a bina string.

Duchenne-type muscular dystrophy is due to mutations in the gene, located on the X chromosome, encoding the protein dystrophin. 

Suwa Y, WE Olben, LJ Eorney (1996) Characterization of chromosomally encoded 2,4-dichlorophenoxyace-tic acid-a-ketoglutarate dioxygenase from Burkholderia sp. strain RASC. Appl Environ Microbiol 62 2464-2469. 

M19. Michelson, A. M Markham, A. F and Orkin, S. H Isolation and DNA sequence of a full-length cDNA clone for human X-chromosome-encoded phosphoglycerate kinase. Proc. Natl. Acad. Sci. U.S.A. 80,472-476 (1983). 

The circular mitochondrial chromosome encodes 13 of the more than 80 proteins that comprise the major complexes of oxidative phosphorylation as well as 22 tRNAs and 2 rRNAs. Mutations in these genes affect highly aerobic tissues (nerves, muscle), and the diseases exhibit characteristic mitochondrial pedigrees (maternal inheritance). 

First generation Examples are cephalothin, cefazolin, cephalexin, cefadroxil, cephradine, cephaloglycine which are like penicillins but in general, resistant to majority of the plasmid encoded class A fylactamases but not to chromosomal encoded class C broader spectrum fylactamases. 

These substances resemble 3-lactam molecules (Figure 43-7) but they have very weak antibacterial action. They are potent inhibitors of many but not all bacterial 3 lactamases and can protect hydrolyzable penicillins from inactivation by these enzymes. -Lactamase inhibitors are most active against Ambler class A lactamases (plasmid-encoded transposable element [ ] lactamases in particular), such as those produced by staphylococci, H influenzae, N gonorrhoeae, salmonella, shigella, E coli, and pneumoniae. They are not good inhibitors of class lactamases, which typically are chromosomally encoded and inducible, produced by enterobacter, citrobacter, serratia, and pseudomonas, but they do inhibit chromosomal 3 lactamases of bacteroides and moraxella. 

Charles, T.C. Nester, E.W. A chromosomally encoded two-component sensory transduction system is required for virulence of Agrobacterium tumefaciens. J. Bacteriol., 175, 6614-6625 (1993)... 

Numerous episodes have occurred in which humans have developed drug-resistant nontyphoid Salmonella infections that have been traced to animal sources (23). These bacteria can be transmitted to humans in food or through direct contact with animals. Antimicrobial resistance limits the tlierapeutic options available to veterinarians and physicians for the subset of clinical cases of nontyphoid Salmonella that require treatment. A recent example is a clone of Salmonella typhimurium DT 104 with chromosomally encoded resistance to ampicillin, tetracycline, streptomycin, chloramphenicol and sulfonamides, which has become increasingly common in humans in England and Wales since 1990 (24). Since 1992, only Salmonella enteritidis has accounted for more cases of human salmonellosis than Salmonella typhimurium DT 104 (25, 26). Multiresistant DT 104 has currently emerged in several European countries (27-29) outbreaks have been also reported in the United States in both cattle (30) and humans (31). 

Algorithm GASP uses a genetic algorithm that iteratively optimizes a population of chromosomes according to the fitness function described here below [16]. Each chromosome encodes angles of rotations about flexible bonds and mappings between features. 

In the United States, the RDA for Se is 55 /xg. Estimated intakes of Se by most of U.S. residents exceed that value, whereas in Europe the daily intake is sometimes lower than 30 mg, and in some rural regions of China it is < 10 mg (84). The reduced dietary intake has to be considered together with a possible polymorphism that may result in a different requirement of Se or with the loss of chromosomes encoding selenoproteins, during the transformation of a premalignant cell to the cancer cell (89). Se baseline levels of the subjects participating in clinical studies were very different (84) and consequently a fixed supplementation may end up with different outcomes. 

Figure 1.15. GA-based principal component analysis (PCA) of descriptor combinations. The chromosome encodes single descriptors and calculation parameters for PCA ( PCs, number of principal components Bins, number of bins per component axis)...

Pseudomonas putida FI (which contains a chromosomally encoded tod operon for toluene degradation) was genetically modified by the introduction of tod-lux CDABE into the chromosome yielding the biosensor Pseudomonas putida TVA8 (Applegate et al., 1998). The tod operon is induced when exposed to several compounds such as benzene, toluene, ethylbenzene and xylene (Shingleton et al., 1998). 

A complete sequence of DNA bases, or chromosome, encodes instructions including those required by a complex supramolecular protein assembly, the ribosome, to form the extensive proteins that control much of biological structure and... 

Plasmid- and transposon-mediated resistance to trimethoprim involves a by-pass of the sensitive step by duplication of the chromosomally-encoded dihydrofolate reductase (DHFR) target enzyme [203]. Several trimethoprim-resistant bacterial DHFRs have been identified, resistance ensuing because of altered enzyme target sites [204], Low-level resistance to tetracyclines arises in E. coli as a result of chromosomal mutations leading to loss of the outer membrane porin OmpF through which these drugs normally pass [6, 193],... 

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