Control of lysogeny and immunity of Bacillus subtilis temperate bacteriophage SP beta by its d gene.

The d gene from the Bacillus subtilis temperate bacteriophage SP beta was isolated. When introduced into an SP beta-sensitive strain of B. subtilis, the cloned d gene directed the synthesis of a 22-kilodalton protein and conferred on the host immunity to SP beta phage.

The PEP4 gene encodes an aspartyl protease implicated in the posttranslational regulation of Saccharomyces cerevisiae vacuolar hydrolases.

pep4 mutants of Saccharomyces cerevisiae accumulate inactive precursors of vacuolar hydrolases. The PEP4 gene was isolated from a genomic DNA library by complementation of the pep4-3 mutation. Deletion analysis localized the complementing activity to a 1.

Molecular cloning of a complementary DNA encoding human macrophage-specific colony-stimulating factor (CSF-1).

Complementary DNA (cDNA) clones encoding human macrophage-specific specific colony-stimulating factor (CSF-1) were isolated. One cDNA clone codes for a mature polypeptide of 224 amino acids and a putative leader of 32 amino acids. This cDNA, which was cloned in the Okayama-Berg expression vector, specifies the synthesis of biologically active CSF-1 in COS cells, as determined by a specific radioreceptor assay, macrophage bone marrow colony formation, and antibody neutralization.

Molecular cloning of the complementary DNA for human tumor necrosis factor.

Tumor necrosis factor (TNF) is a soluble protein that causes damage to tumor cells but has no effect on normal cells. Human TNF was purified to apparent homogeneity as a 17.3-kilodalton protein from HL-60 leukemia cells and showed cytotoxic and cytostatic activities against various human tumor cell lines.

Targeted mutagenesis in vitro: lac repressor mutations generated using AMV reverse transcriptase and dBrUTP.

We have cloned the gene for the lac operon repressor (lacI) of Escherichia coli into the M13 related phage f1. Mutagenesis of the lacI gene was performed in vitro by filling dsDNA molecules gapped over the lacI gene with Avian Myeloblastosis Virus (AMV) reverse transcriptase. LacI mutants are found at a frequency of 1 in 10(4) using a genetic screen in vivo.