Vector bacterial

Hybrid vector Bacterial plasmid component Yeast nuclear component Yeast plasmid component... 

In general, fungal mycelia are filtered relatively easily, because mycelia filter cake has sufficiently large porosity. Yeast and bacteiia are much more difficult to handle because of thefr small size. Alternative filtration methods, which eliminate the filter cake, are becoming more acceptable for bacterial and yeast separation. Micro-filtration is achieved by developing large cross-flow fluid velocities across the filter surface while the velocity vector normal to the surface is relatively small. Build up of filter cake and problems of high cake resistance are therefore prevented. Micro-filtration is not discussed in this section. 

A Bacterial Artificial Chromosome (BAC) is a vector that allows the propagation of larger exogenous DNA fragments, up to several hundred kb. BACs are propagated in recombination-deficient strains of E. coli. They are more stable and easier to handle than yeast artificial chromosomes (YACs). 

Bacterial plasmids are small, circular, duplex DNA molecules whose natural function is to confer antibiotic resistance to the host cell. Plasmids have several properties that make them extremely useful as cloning vectors. They exist as single or multiple copies within the bacterium and replicate independently from the bacterial DNA. The complete DNA sequence of many plasmids is known hence, the precise location of restriction enzyme... 

Fig. 24.5 Insertion of a cloned insulin gene into a vector carrying a bacterial promoter. The arrow indicates the direction of transcription. If we suppose the bacterial promoter is derived from the lactose operon then transcription will be initiated only in the presence of lactose.

Fig. 1 Schematic outline of procedures employed in the synthesis of a cDNA gene copy from a polyadenylated mRNA template, insertion of the cDNA into a bacterial plasmid vector by a homopolymer tailing strategy, and cloning of the recombinant plasmid in an Escherichia coli host.

Other pattern recognition strategies have been used for bacterial identification and data interpretation from mass spectra. Bright et al. have recently developed a software product called MUSE, capable of rapidly speciating bacteria based on matrix-assisted laser desorption ionization time-of-flight mass spectra.13 MUSE constructs a spectral database of representative microbial samples by using single point vectors to consolidate spectra of similar (not identical) microbial strains. Sample unknowns are then compared to this database and MUSE determines the best matches for identification purposes. In a... 

Plasmids are small, circular DNAs that range in size from 2 to approximately 100 kb. They also can be amplified to approximately 20 copies per cell. In addition, plasmids can be introduced into bacterial cells, although less efficiently than phage vectors. Some plasmids can be used to introduce recombinant DNA into yeast cells. 

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