Abstract：
:Restriction modification (RM) systems serve to protect bacteria against bacteriophages. They comprise a restriction endonuclease activity that specifically cleaves DNA and a corresponding methyltransferase activity that specifically methylates the DNA, thereby protecting it from cleavage. Such systems are very common in bacteria. To find out whether the widespread distribution of RM systems is due to horizontal gene transfer, we have compared the codon usages of 29 type II RM systems with the average codon usage of their respective bacterial hosts. Pronounced deviations in codon usage were found in six cases: EcoRI, EcoRV, KpnI, SinI, SmaI, and TthHB81. They are interpreted as evidence for horizontal gene transfer in these cases. As the methodology is expected to detect only one-fourth to one-third of all horizontal gene transfer events, this result implies that horizontal gene transfer had a considerable influence on the distribution and evolution of RM systems. In all of these six cases the codon usage deviations of the restriction enzyme genes are much more pronounced than those of the methyltransferase genes. This result suggests that in these cases horizontal gene transfer had occurred sequentially with the gene for the methyltransferase being first acquired by the cell. This can be explained by the fact that an active restriction endonuclease is highly toxic in cells whose DNA is not protected from cleavage by a corresponding methyltransferase.
journal_name
J Mol Evoljournal_title
Journal of molecular evolutionauthors
Jeltsch A,Pingoud Adoi
10.1007/BF02198833subject
Has Abstractpub_date
1996-02-01 00:00:00pages
91-6issue
2eissn
0022-2844issn
1432-1432journal_volume
42pub_type
杂志文章abstract：:DNA sequences representing approximately 40% of the large-subunit rRNA gene from the lower dipteran Chironomus thummi were analyzed. Once aligned with their Drosophila counterparts, sequence and base content comparisons were carried out. Sequence identity was found to be high overall, except for six regions that displ...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF00173183
更新日期：1995-12-01 00:00:00
abstract：:Fimbrial adhesins allow bacteria to interact with and attach to their environment. The bacteria possibly benefit from these interactions, but all external structures including adhesins also allow bacteria to be identified by other organisms. Thus adhesion molecules might be under multiple forms of selection including ...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s002390010148
更新日期：2001-02-01 00:00:00
abstract：:The semen of many primate species coagulates into a mating plug believed to prevent the sperm of subsequent mating events from accessing the ova. The texture of the coagulum varies among species: from a semisoft mass in humans to a firm plug in chimpanzees. In humans, a component of the coagulum, semenogelin I, also i...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-002-2463-0
更新日期：2003-08-01 00:00:00
abstract：:Hypothetical Products from Noncoding Frames (i.e., HyPNoFs) are hypothetical, not-coded proteins, translated from alternate reading frames (i.e., coding + 1 and coding + 2) of cDNAs. HyPNoFs of CD4, PKC, oncostatin, bcl-2 proto-oncogene, tumor suppressor p53, cystic fibrosis transmembrane regulator (CFTR), and tumor n...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF00160503
更新日期：1995-06-01 00:00:00
abstract：:As illustrated by the mitochondrion and the eukaryotic cell, little in biology makes sense except in light of mutualism. Mutualisms are persistent, intimate, and reciprocal exchanges; an organism proficient in obtaining certain benefits confers those on a partner, which reciprocates by conferring different benefits. M...
journal_title：Journal of molecular evolution
pub_type： 杂志文章,评审
doi：10.1007/s00239-017-9804-x
更新日期：2017-08-01 00:00:00
abstract：:Polymerization of various nucleoside-5'-phosphorimidazolides has been conducted in neutral aqueous solution using divalent metal ions as catalysts. Oligonucleotide formation took place from each of the ribonucleoside-5'-phosphorimidazolides, ImpC, ImpU, ImpA, ImpG, and ImpI. The yields and distributions of the resulti...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF02100072
更新日期：1988-01-01 00:00:00
abstract：:Multiple genes of the hoatzin encoding stomach lysozyme c and closely related members of this calcium-binding lysozyme c group were cloned from a genomic DNA library and sequenced. There are a minimum of five genes represented among these sequences that encode two distinct groups of protein sequences. One group of thr...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF02338801
更新日期：1996-06-01 00:00:00
abstract：:A long-standing hypothesis posits that morphological changes may be more likely to result from changes in regulation of gene expression than from changes in the protein coding sequences of genes. We have compared the expression pattern of the twisted gastrulation (tsg) gene among five Drosophila species: D. melanogast...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/pl00006293
更新日期：1998-02-01 00:00:00
abstract：:Natural populations of the Midas cichlid species in several different crater lakes in Nicaragua exhibit a conspicuous color polymorphism. Most individuals are dark and the remaining have a gold coloration. The color morphs mate assortatively and sympatric population differentiation has been shown based on neutral mole...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-010-9340-4
更新日期：2010-05-01 00:00:00
abstract：:Circadian clock genes are remarkably conserved between eucoelomates. Although Drosophila has one copy of each major component, vertebrates have two or (in the case of the Period genes) three paralogs (Per1-3). We investigated the possibility that the vertebrate Per genes arose through two genome duplications during th...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-005-0185-1
更新日期：2006-06-01 00:00:00
abstract：:Computational and experimental attempts tried to characterize a universal core of genes representing the minimal set of functional needs for an organism. Based on the increasing number of available complete genomes, comparative genomics has concluded that the universal core contains < 50 genes. In contrast, experiment...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-005-0250-9
更新日期：2006-12-01 00:00:00
abstract：:The evolutionary relationships of four eukaryotic kingdoms--Animalia, Plantae, Fungi, and Protista--remain unclear. In particular, statistical support for the closeness of animals to fungi rather than to plants is lacking, and a preferred branching order of these and other eukaryotic lineages is still controversial ev...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF02198844
更新日期：1996-02-01 00:00:00
abstract：:The complete or partial sequences of 47 E. coli ribosomal proteins described in the literature have been examined by computerized search and matching programs. In contrast to results previously reported by other investigators, sequence homologies were uncovered among some of these ribosomal proteins that are well beyo...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF01732666
更新日期：1980-05-01 00:00:00
abstract：:Several studies in Drosophila have shown a paucity of male-biased genes (i.e., genes that express higher in males than in females) on the X chromosome. Dosage compensation (DC) is a regulatory mechanism of gene expression triggered in males that hypertranscribes the X-linked genes to the level of transcription in fema...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-016-9735-y
更新日期：2016-05-01 00:00:00
abstract：:The finding that ribozymes can catalyze RNA chain elongation has led to the proposal that an early self-replicating system could have consisted of RNA alone. In such a chain elongation reaction, the Tetrahymena ribozyme was found to select 3',5'-linked substrates from a pool that contained a large molar excess of 2',5...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF02602919
更新日期：1989-12-01 00:00:00
abstract：:Phylogenetic relationships of nematodes, nematomorphs, kinorhynchs, priapulids, and some other major groups of invertebrates were studied by 18S rRNA gene sequencing. Kinorhynchs and priapulids form the monophyletic Cephalorhyncha clade that is the closest to the coelomate animals. When phylogenetic trees were generat...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/pl00006416
更新日期：1998-11-01 00:00:00
abstract：:Males of three inbred lines of Drosophila melanogaster were heat-shocked 90 min at 37 degrees C. The progenies from treated and untreated males mated with untreated females of the same line were checked for their chromosomal insertion patterns of various mobile elements by either in situ hybridization or Southern blot...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF02603073
更新日期：1989-05-01 00:00:00
abstract：:Cot and chemical analysis show that the haploid genome size of Thermobia domestica is 3-4x10(9) nucleotide pairs. Of this DNA 33% is single copy sequences and 67% is repetitive sequences. The repetitive sequences are predominantly 300 nucleotides in length and are interspersed among the single copy sequences in a shor...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF01733135
更新日期：1980-08-01 00:00:00
abstract：:In bacteria, synonymous codon usage can be considerably affected by base composition at neighboring sites. Such context-dependent biases may be caused by either selection against specific nucleotide motifs or context-dependent mutation biases. Here we consider the evolutionary conservation of context-dependent codon b...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s002399910031
更新日期：2000-03-01 00:00:00
abstract：:A general correlation between neural expression and negative charge in isozymes suggests charge represents an adaptation to the neural environment. Interestingly, a notable exception exists in teleost fish. Two cytosolic malate dehydrogenase (MDH) isozymes have different spatial expression patterns in certain fishes: ...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-002-2398-x
更新日期：2003-03-01 00:00:00
abstract：:Intron-encoded U17 RNA is a member of the H/ACA box class of small nucleolar RNAs (snoRNAs) involved in ribosomal RNA (rRNA) maturation. U17 snoRNA shows typical characteristics of guide RNAs, which specify sites of pseudouridylation on the precursor rRNA (pre-rRNA). However, in spite of the presence of H and ACA boxe...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-001-0065-2
更新日期：2002-02-01 00:00:00
abstract：:Comparisons of the amino acid compositions of the nitrogenase proteins from different organisms and their correlation with cross-reactivities and taxonomical data suggest an evolution within bacterial genomes rather than within plasmids. Comparisons of the amino acid compositions of nitrogenases and other ATP-ases sho...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF01732473
更新日期：1976-03-29 00:00:00
abstract：:An assay based on derivative analysis of thermal denaturation (melting) behavior of reassociated DNA was developed in an attempt to characterize the sequence relationships in repeated DNA families according to the homogeneous or heterogeneous models of Bendich and Anderson (1977). The validity of the technique was con...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF01732678
更新日期：1981-01-01 00:00:00
abstract：:Molluscan shells are composed of calcium carbonates, with small amounts of extracellular matrices secreted from mantle epithelial cells. Many types of shell matrix proteins (SMPs) have been identified from molluscan shells or mantle cells. The pen shell Atrina pectinata (Pinnidae) has two different shell microstructur...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-020-09977-7
更新日期：2020-12-01 00:00:00
abstract：:The sequence of a cloned Anopheles stephensi gene showed 72% inferred amino acid identity with Drosophila melanogaster Dox-A2 and 93% with its putative ortholog in Anopheles gambiae. Dox-A2 is the reported but herein disputed structural locus for diphenol oxidase A2. Database searches identified Dox-A2 related gene se...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s002390010053
更新日期：2000-06-01 00:00:00
abstract：:The specificity of interaction of amino acids with triplets in the acceptor helix stem of tRNA was investigated by means of a statistical analysis of 1400 tRNA sequences. The imprint of a prototypic genetic code at position 3-5 of the acceptor helix was detected, but only for those major amino acids, glycine, alanine,...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF00160461
更新日期：1992-06-01 00:00:00
abstract：:When an aqueous solution (pH 7.0) of 3H deoxythymidine 5'-triphosphate, deoxythymidine 5'-phosphate, 4-amino-5-imidazolecarboxamide, cyanamide and ammonium chloride was dried and heated at 60 degrees C for 18 h, oligomers were obtained in a yield of approximately 80%. After the chemical degradation of any pyrophosphat...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/BF01764595
更新日期：1977-12-29 00:00:00
abstract：:Microsporidia are unicellular eukaryotes living as obligate intracellular parasites. Lacking mitochondria, they were initially considered as having diverged before the endosymbiosis at the origin of mitochondria. That microsporidia were primitively amitochondriate was first questioned by the discovery of microsporidia...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-004-2673-0
更新日期：2004-12-01 00:00:00
abstract：:The mammalian defensin molecule is a short, highly cationic peptide cytotoxic to both microbial and mammalian cells which is cleaved from a precursor including a signal peptide and a highly anionic propiece. A phylogenetic analysis of 28 complete sequences from five mammalian species (mouse, rat, guinea pig, rabbit, a...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/pl00006191
更新日期：1997-06-01 00:00:00
abstract：:It has been argued that downstream enzymes in metabolic pathways are expected to be subject to reduced selective constraint, while upstream enzymes, particularly those at pathway branch points, are expected to exhibit more frequent adaptive substitution than downstream enzymes. We examined whether these expectations a...
journal_title：Journal of molecular evolution
pub_type： 杂志文章
doi：10.1007/s00239-008-9105-5
更新日期：2008-08-01 00:00:00
