PubMed Health⌕ Search

Biomedical subjects

B Watson

Publications and source records attributed to B Watson.

107 records · Page 6Linked to original sources
PubMed1975

Plasmid required for virulence of Agrobacterium tumefaciens.

The irreversible loss of crown gall-inducing ability of Agrobacterium tumefaciens strain C-58 during growth at 37 C is shown to be due to loss of a large plasmid (1.2 X 10-8 daltons). The gene responsible for this high rate of plasmid loss at elevated temperatures seems to be located on the plasmid. In addition, another spontaneous avirulent variant, A. tumefaciens strain IIBNV6 is shown to lack the virulence plasmid which its virulent sibling strain, IIBV7, possesses. Deoxyribonucleic acid reassociation measurements prove that the plasmid is eliminated, not integrated into the chromosome, in both of the avirulent derivatives. Transfer of virulence from donor strain C-58 to avirulent recipient strain A136 results from the transfer of a plasmid, which appears identical to the donor plasmid by deoxyribonucleic acid reassociation measurements. The transfer of virulence in another cross, K27 X A136, was also shown to result from the transfer of a large plasmid. These findings establish unequivocally that the large plasmid determines virulence. Two additional genetic determinants have been located on the virulence plasmid of A. tumefaciens strain C-58: the ability to utilize nopaline and sensitivity to a bacteriocin produced by strain 84. The latter trait can be exploited for selection of avirulent plasmid-free derivatives of strain C-58. The trait of nopaline utilization appears to be on the virulence plasmid also in strains IIBV7 and K27.

Amino Acids↗
PubMedDate not supplied

Cricoarytenoid subluxation, computed tomography, and electromyography findings.

A case of cricoarytenoid subluxation secondary to endotracheal intubation and documented by computed tomography (CT) and electromyography (EMG) is reported. Successful endoscopic reduction of the displaced arytenoid is confirmed by CT. The normal anatomy and physiology of the cricoarytenoid joint is presented and the literature regarding this rarely reported injury is reviewed. Based on this review and the case reported, a treatment plan is proposed.

Arytenoid Cartilage↗