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A Lüttke

Publications and source records attributed to A Lüttke.

10 recordsLinked to original sources
PubMed1994

Codon usage adaptation in the ferredoxin-NADP+ oxidoreductase of Cyanophora paradoxa upon translocation from cyanoplast to nucleus.

Previous investigations of the petH gene of the biflagellated autotrophic protist Cyanophora paradoxa (Cp; Glaucocystophyta), descendant of an original endocyanome (symbiotic consortium of a eukaryote with an endocytobiotic cyanobacterium), established that: (i) the gene coding for a cyanoplast protein (FNR) is located on the nuclear genome; (ii) the sequence of the mature protein shows a high degree of amino-acid conservation to cyanobacterial homologs; (iii) the sequence of the transit peptide of the pre-protein displays poor, if any, homology to counterparts in higher plants. Here, we show that the G+C content and codon usage of this gene are most similar to a genuine nuclear gene. By contrast, the G+C content and codon usage display substantial differences to a collection of 30 cyanoplast encoded genes mainly attributable to alterations in the third codon position. Correspondence analysis on codon preference parameters corroborates the claim of codon usage adaptation of the translocated gene to the nuclear pattern. As a consequence, codon usage distances of genes of Cp encoded either by the nucleus or the cyanoplasts vs. homologous genes of the cyanobacterium, Anabaena, are notably different; this result has important phylogenetic implications.

Adaptation, Physiological↗
PubMed1993

Sequence analysis of pre-ferredoxin-NADP(+)-reductase cDNA from Cyanophora paradoxa specifying a precursor for a nucleus-encoded cyanelle polypeptide.

A cDNA clone for pre-ferredoxin-NADP+ reductase (FNR) was obtained by screening a Cyanophora paradoxa expression library with antibodies specific for cyanelle FNR. The 1.4 kb transcript was derived from a single-copy gene. The precursor (41 kDa) and mature forms (34 kDa) of FNR were identified by western blotting of in vitro translation products and cyanelle extracts, respectively. The derived amino acid sequence of the mature form was corroborated by data from N-terminal protein sequencing and yielded identity scores from 58% to 62% upon comparison with cyanobacterial FNRs. Sequence conservation seemed to be even more pronounced in comparison with enzymes from higher plants, but using the neighbor joining method the C. paradoxa sequence was clearly positioned between the prokaryotic and eukaryotic sequences. The transit peptide of 65 or 66 amino acids appeared to be totally unrelated to those from spinach, pea and ice plant but showed overall characteristics of stroma-targeting peptides.

Amino Acid Sequence↗
PubMed1993

MacP12: a protein property multi-profile plot program for the Apple Macintosh.

MacP12, a program for the Apple Macintosh, allows simultaneous plotting of two protein property profiles selectable from 12 built-in amino acid property scales. Various parameters such as the region to be analyzed, the size of the sliding window, the weighting function and the size of the graphical output can be easily adjusted by the user, which makes this program appropriate for diverse research questions. Since built-in scales can be simply exchanged, MacP12 is adaptable to the specific needs of the individual user.

Computer Graphics↗
PubMed1992

MacT: Apple Macintosh programs for constructing phylogenetic trees.

MacT is a set of programs for the Apple Macintosh to construct and evaluate unrooted trees derived from amino acid sequences using a distance matrix method. Programs are designed on a 'one program--one task' basis for (i) determining the branching order in trees consisting of four or five species and calculating various statistical measures, (ii) calculating statistical measures for all possible topologies of unrooted trees and (iii) generating and evaluating trees derived from bootstrapped samples. With four auxiliary programs unrooted trees can be built for maximal 26 species, and the robustness of topologies be tested by bootstrapping.

Algorithms↗
PubMed1990

MacPROT: a set of BASIC programs for protein structure analysis.

MacPROT is a set of seven interactive application programs and a coordinating menu for storing, editing, and analysing protein sequences. Analyses for hydropathy, amphilicity, helix wheel, and dot matrix comparison are plotted as graphs on the screen and can be printed immediately or transferred to a picture accepting program. Programs are written in BASIC for the Apple 512 kbyte Macintosh. The source code is accessible and can be adapted to other machines.

Amino Acid Sequence↗
PubMed1982

Apicobasal gradient of chloroplast DNA synthesis and distribution in Acetabularia.

Autoradiographic and biochemical experiments have revealed the presence, in vegetative cells of Acetabularia, of an apicobasal gradient of penetration and incorporation of labelled DNA precursors into the chloroplasts. Staining of chloroplasts with the DNA-specific fluorochrome DAPI has shown that the number of chloroplasts without DNA increases from the apex towards the base of the cell. All together, our findings support the existence of an apicobasal gradient of chloroplast DNA synthesis and distribution in Acetabularia.

Acetabularia↗
PubMedDate not supplied

Ferredoxin-NADP+ oxidoreductase of C. paradoxa nucleus encoded, but cyanobacterial gene transfer from symbiont to host, an evolutionary mechanism originating new species.

The nucleus encoded cyanoplast ("cyanellar") ferredoxin-NADP + oxidoreductase (FNR) of Cyanophora paradoxa, characterized by an N-terminal amino acid sequence, is compared with homologous sequences of other photoautotrophic organisms. The high degree of similarity to the cyanobacterial sequences indicates a cyanobacterial origin. This could be a first direct demonstration of an intertaxonic combination: a gene transfer from an original endocytobiont (cyanobacterium) to the nucleus of its host, one of the most important demands of the Endosymbiosis Theory, an evolutionary mechanism leading to the origin of a new species.

Amino Acid Sequence↗