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W Lindenmaier

Publications and source records attributed to W Lindenmaier.

28 records · Page 2Linked to original sources
PubMed1979

Isolation and characterization of the chicken ovomucoid gene.

The chicken ovomucoid gene has been isolated by screening a chicken DNA library with a plasmid containing ovomucoid mRNA sequences. Twelve recombinant phages carrying ovomucoid mRNA sequences were isolated. Two of them, extending farthest into the 5' and 3' direction respectively, were characterized by restriction mapping and Southern hybridization as well as by electron microscopic analysis of hybrids between the cloned DNA and ovomucoid mRNA. Seven intervening sequences interrupt the ovomucoid mRNA sequence in chromosomal DNA. From these data a minimal size of 5.6 kb can be estimated for the length of the ovomucoid gene.

Animals↗
PubMed1979

Arrangement of coding and intervening sequences of chicken lysozyme gene.

Hybrid phages that contain chicken lysozyme gene sequences have been isolated from a chicken DNA library. Two overlapping clones covering a region of 22 kilobase pairs around this gene have been studied by restriction mapping. Southern hybridization, and electron microscopic analysis of hybrids between lysozyme mRNA and the cloned cellular DNA. Three intervening sequences interrupt the lysozyme structural gene. The cellular gene is at least 3.9 kilobases long, about 6 times the length of the structural gene.

Animals↗
PubMed1978

The expression of tetracycline resistance after insertion of foreign DNA fragments between the EcoRI and HindIII sites of the plasmid cloning vector pBR 322.

In vitro recombination techniques were used to construct hybrid plasmids between pBR 322 and different DNA fragments derived from pML 21 and the E. coli chromosome. Some of the resulting hybrid plasmids express the tetracycline resistance gene of pBR 322, depending on the DNA fragment which has been ligated into the HindIII-site of pBR 322. From these studies we could conclude the direction of transcription of the kanamycin resistance gene in plasmid pML 21 with respect to the SalI, SmaI, HincII, KpnI, EcoRI and HindIII restriction sites. The replacement of the small HindIII-EcoRI-fragment in pBR 322 by other DNA fragments from the E. coli chromosome and selection for tcr-phenotypes showed that this system may be very useful for screening and analysis of promotor-containing DNA fragments.

DNA, Bacterial↗
PubMed1978

Cloning of chicken lysozyme structural gene sequences synthesized in vitro.

Double-stranded chicken lysozyme cDNA was synthesized from an oviduct mRNA fraction enriched for lysozyme mRNA. The ds-cDNA was inserted into the BamHI site of plasmid pBR322 using chemically synthesized DNA linker molecules containing the BamHI restriction endonuclease cleavage site. After bacterial transformation, colonies carrying lysozyme DNA were identified by hybridization with highly purified lysozyme cDNA. The 555 base pairs long cloned DNA fragment of one recombinant plasmid was isolated and characterized by restriction endonuclease digestion. The DNA sequence of selected parts of the inserted DNA is as predicted from the amino acid sequence of prelysozyme. The sequence data allows the unambiguous location of the coding region within lysozyme mRNA.

Animals↗
PubMed1977

Transposition and insertion of intact, deleted and enlarged ampicillin transposon Tn3 from mini-R1 (Rsc) plasmids into transfer factors.

The miniR1-(Rsc)-plasmids which derive from the copy mutant R1drd-19B2 (pKN102) are non-conjugative extrachromosomal elements which can not be co-transferred by various transfer factors to recipient strains under standard mating conditions. The attempts to mobilize Rsc11 by F'lac lead to transconjugants carrying F'lac::Tn3 with Tn3 mainly inserted into the lac operon. In addition it can be shown that Rsc11 can become inserted as a complete unit into the transfer factor giving rise to rather unstable recombinant intermediates. Dissociation of these intermediates may lead to alterations of the original plasmids. The Tn3 part of Rsc13 can be enlarged or deleted by in vitro manipulations. In vitro insertion of EcoRI-fragments into an EcoRI+ site of Tn3 leads to new transposable units which can be transposed to the RTF part of R1. This new genetic entity can be stably integrated into the chromosome of E. coli by integrative suppression of a dnaAts-mutation. Deletions at one end or the central region of Tn3 abolish the capability of transposition. However, the Rsc-plasmids containing the deleted Tn3 can still be inserted into the transfer factor as complete units. The resulting recombinants are unstable leading after dissociation in some cases to new plasmids with altered properties.

Ampicillin↗
PubMed1977

Properties of hybrid plasmids, consisting of parts of the mini-R1 factor Rsc11 and ColE1.

In vitro joining of the two small multicopy plasmids Rsc11 and ColE1 by a poly dAdT linker resulted in hybrid plasmids, which determine resistance to ampicillin and immunity to colicin E1. Isolation of the plasmid DNA from single colonies revealed that a variety of hybrid plasmids was formed. Cleavage of these plasmids with restriction endonucleases HinII, HindIII, EcoRI, SmaI and BamI and hybridization with ColE1 demonstrated that they contain different parts of the parent plasmids, Rsc11 and ColE1. Their copy number in the cell is between 6 and 15 per chromosome depending on the plasmid. None of these plasmids can replicate in polA mutants. Replication continues in the presence of chloramphenicol. This suggests that replication can only occur from the ColE1 origin and that the replication function of the Rsc11 part is lost. The hybrid plasmids are compatible with Rsc11 but not with ColE1. The comparison of the physical maps of these Rsc11--ColE1 hybrids with their functions allows a partial determination of the location of ampicillin resistance, replication and incompatibility on the Rsc11 genome.

Ampicillin↗
PubMed1974

Plasmids controlling synthesis of hemolysin in Escherichia coli: molecular properties.

Covalently closed extrachromosomal deoxyribonucleic acid (DNA) was isolated from alpha-hemolytic wild-type strains of Escherichia coli. Most strains examined were able to transfer the hemolytic property with varying frequencies to nonhemolytic recipient strains. Out of eight naturally isolated alphahemolytic E. coli strains, four contained a set of three different supercoiled DNAs with sedimentation coefficients of 76S (plasmid A), 63S (plasmid B), and 55S (plasmid C). The sedimentation coefficients and the contour lengths of the isolated molecules correspond to molecular weights of 65 x 10(6), 41 x 10(6), and 32 x 10(6). Three alpha-hemolytic wild-type strains carried only one plasmid with a molecular weight of 41 x 10(6), and one strain harbored two plasmids with molecular weights of 41 x 10(6) and 32 x 10(6). Alpha-hemolytic transconjugants were obtained by conjugation of E. coli K-12 with the hemolytic wild-type strains. A detailed examination revealed that plasmids with the same sizes as plasmids B and C of the wild-type strains can be transferred separately or together to the recipients. Both plasmids possess the hemolytic determinant and transfer properties. Plasmid A appears to be, at least in one wild-type strain, an additional transfer factor without a hemolytic determinant. In one case a hemolytic factor was isolated, after conjugation, that is larger in size than plasmid A and appears to be a recombinant of both plasmids B and C.

Centrifugation, Density Gradient↗