Strain defect

It was surmised that X-ray-induced base damage would lead mostly to recessive lesions and that the significant damage in cells other than haploids was, therefore, of a different nature. In due course, it was shown that the principal agent of lethality was the formation of double-strand breaks, since in strains defective in doublestrand break repair, inactivation and the induction of double-strand breaks were in a 1 1 ratio (Ho, 1975). 

Stefan, A., Radeghieri, A., Gonzalez Vara y Rodriguez, A., Hochkoeppler, A. (2001), Directed evolution of (3-galactosidase from Escherichia coli by mutator strains defective in the 3 —>5 exonudease activity of DNA polymerase III, FEBS Lett. 493, 139-143. 

Lattice dynamics in bulk perovskite oxide ferroelectrics has been investigated for several decades using neutron scattering [71-77], far infrared spectroscopy [78-83], and Raman scattering. Raman spectroscopy is one of the most powerful analytical techniques for studying the lattice vibrations and other elementary excitations in solids providing important information about the stmcture, composition, strain, defects, and phase transitions. This technique was successfully applied to many ferroelectric materials, such as bulk perovskite oxides barium titanate (BaTiOs), strontium titanate (SrTiOs), lead titanate (PbTiOs) [84-88], and others. 

The cyanobacterium, Synechocystis PCC 6803, is transformabie and has the ability to grow photoheterotrophicaiiy (1), thus ailowing strains defective in PS li function to be constructed and studied, in order to monitor the effects of specific mutations in the psbA. psbD and iJstlC genes, which code for the poiypeptides D1, D2 and CP43, respectiveiy, we have deveioped a procedure for the isoiation of PS II core complexes. 

Luo LH, Seo JW, Oh BR, Seo PS, Heo SY, Hong WK, Kim DH, Chul HK. (2011). Stimulation of reductive glycerol metabolism by overexpression of an aldehyde dehydrogenase in a recombinant Klebsiella pneumoniae strain defective in the oxidative pathway. / Ind Microbiol Biotechnol, 38, 991-999. 

Bianchi MM, Brambilla L, Protani F, Liu CL, Lievense J, Porro D. (2001). Efficient homo-lactic fermentation by Klityveromyces lactis strains defective in pyruvate utilization and transformed with the heterologous LDH gene. Appl Envion Microbiol, 67,5621-5625. 

By reducing the tension in the vertical tows of the shape in the zone where tow buckles may take place, the too high strain defect was also reduced to such an extent that it is not a problem anymore. 

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