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A mutation in the tolC(mtcB) gene of Escherichia coli K12 results in increased sensitivity to sodium dodecylsulfate (SDS), sodium deoxycholate, basic dyes, mitomycin C, and bleomycin, and makes the cell tolerant to the killing action of colicin E1. From lysogens with lambda cI857S7 integrated at a secondary attachment site, a transducing phage (lambda dtolC+) that transduces a tolC recipient to SDS resistance was isolated. A recombinant DNA molecule was constructed in vitro from plasmid pBR322 as a vector, and an EcoRI-BamHI fragment of lambda tolC+ DNA. The resulting plasmid, designated pOK1, was 5.6 megadaltons (Md). The tolC bacteria transformed with plasmid pOK1 restored the TolC+ phenotype with regard to mitomycin C, SDS, and colicin E1 sensitivities. A plasmid with an amber mutation in the tolC gene, designated pOK18, was isolated by the same procedure used for the isolation of pOK1. The plasmid had a molecular weight of 5.6 Md and produced the same size of DNA fragments as the tolC+ plasmid, pOK1, after digestion with the indicated restriction enzymes. The plasmid, pOK18, conferred the TolC+ phenotype when introduced into a tolC strain in the presence of, but not the absence of, an amber suppressor. Plasmid-specified polypeptides were determined by using maxicells of strains uvrA recAsup+ and uvrA recA tyrT, containing each plasmid. Three additional proteins of 54,000 (54K), 29K, and 27K were produced in maxicells containing pOK1. These three proteins were synthesized in maxicells of the uvrA recA tyrT strain carrying pOK18, whereas synthesis of the 54K protein by pOK18 did not take place in maxicells of the uvrA recA sup+ strain, although the other two proteins were produced in normal amounts. From these results we concluded that the product of the tolC gene is a protein with a molecular weight of 54K.

We have studied the prognostic factors of 117 cases of unresected adenocarcinoma of the lung, and have examined these cases according to the following categories: age, sex, clinical stage, performance status (P.S.), serum albumin on admission, serum CEA, the presence of complication, the present status of an abnormal chest shadow from a year ago at the same location, and differentiation of cells. Significant differences were detected in the P.S., the serum albumin and the presence of complications by survival analysis through the use of covariate-Cox models. We also have noted that the difference between stage I and the other stages of the clinical stage was found to be significant by a generalized Wilcoxon test. In conclusion, the determining prognostic factors of an unresected adenocarcinoma of the lung are the P.S., the serum albumin, the presence of complications and the clinical stage.