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1.
Christiane Elie Marie- France Baucher Christian Fondrat Patrick Forterre 《Journal of molecular evolution》1997,45(1):107-114
We have isolated a new gene encoding a putative 103-kDa protein from the hyperthermophilic archaeon Sulfolobus acidocaldarius. Analysis of the deduced amino-acid sequence shows an extended central domain, predicted to form coiled-coil structures, and
two terminal domains that display purine NTPase motifs. These features are reminiscent of mechanochemical motor proteins which
use the energy of ATP hydrolysis to move specific cellular components. Comparative analysis of the amino-acid sequence of
the terminal domains and predicted structural organization of this putative purine NTPase show that it is related both to
eucaryal proteins from the ``SMC family' involved in the condensation of chromosomes and to several bacterial and eucaryal
proteins involved in DNA recombination/repair. Further analyses revealed that these proteins are all members of the so called
``UvrA-related NTP-binding proteins superfamily' and form a large subgroup of motor-like NTPases involved in different DNA
processing mechanisms. The presence of such protein in Archaea, Bacteria, and Eucarya suggests an early origin of DNA-motor
proteins that could have emerged and diversified by domain shuffling.
Received: 29 June 1996 / Accepted: 28 February 1997 相似文献
2.
F Lindberg J M Tennent S J Hultgren B Lund S Normark 《Journal of bacteriology》1989,171(11):6052-6058
The product of the papD gene of uropathogenic Escherichia coli is required for the biogenesis of digalactoside-binding P pili. Mutations within papD result in complete degradation of the major pilus subunit, PapA, and of the pilinlike proteins PapE and PapF and also cause partial breakdown of the PapG adhesin. The papD gene was sequenced, and the gene product was purified from the periplasm. The deduced amino acid sequence and the N-terminal sequence obtained from the purified protein revealed that PapD is a basic and hydrophilic peripheral protein. A periplasmic complex between PapD and PapE was purified from cells that overproduced and accumulated these proteins in the periplasm. Antibodies raised against this complex reacted with purified wild-type P pili but not with pili purified from a papE mutant. In contrast, anti-PapD serum did not react with purified pili or with the culture fluid of piliated cells. However, this serum was able to specifically precipitate the PapE protein from periplasmic extracts, confirming that PapD and PapE were associated as a complex. It is suggested that PapD functions in P-pilus biogenesis as a periplasmic transport protein. Probably PapD forms complexes with pilus subunits at the outer surface of the inner membrane and transports them in a stable configuration across the periplasmic space before delivering them to the site(s) of pilus polymerization. 相似文献
3.
Gene structure of a chlorophyll a/c-binding protein from a brown alga: Presence of an intron and phylogenetic implications 总被引:5,自引:0,他引:5
Lise Caron Dominique Douady Michelle Quinet-Szely Susan de Goër Claire Berkaloff 《Journal of molecular evolution》1996,43(3):270-280
A Laminaria saccharina genomic library in the phage EMBL 4 was used to isolate and sequence a full-length gene encoding a fucoxanthin-chlorophyll
a/c-binding protein. Contrary to diatom homologues, the coding sequence is interrupted by an intron of about 900 bp which
is located in the middle of the transit peptide. The deduced amino acid sequence of the mature protein is very similar to
those of related proteins from Macrocystis pyrifera (Laminariales) and, to a lesser extent, to those from diatoms and Chrysophyceae. Seven of the eight putative chlorophyll-binding
amino acids determined in green plants are also present. Alignments of different sequences related to the light-harvesting
proteins (LHC) demonstrate a structural similarity among the three transmembrane helices and suggest a unique ancestral helix
preceded by two β-turns. The β-turns are conserved in front of the second helices of the chlorophyll a/c proteins more so
than in chlorophyll a/b proteins. Phylogenetic trees generated from sequence data indicate that fucoxanthin-chlorophyll-binding
proteins diverged prior to the separation of photosystem I and photosystem II LHC genes of green plants. Among the fucoxanthin-containing
algae, LHC I or II families could not be distinguished at this time.
Received: 14 February 1996 / Accepted: 4 April 1996 相似文献
4.
In the search for the essential functional domains of the large mechanosensitive ion channel (MscL) of E. coli, we have cloned several mutants of the mscL gene into a glutathione S-transferase fusion protein expression system. The resulting mutated MscL proteins had either amino
acid additions, substitutions or deletions in the amphipathic N-terminal region, and/or deletions in the amphipathic central
or hydrophilic C-terminal regions. Proteolytic digestion of the isolated fusion proteins by thrombin yielded virtually pure
recombinant MscL proteins that were reconstituted into artificial liposomes and examined for function by the patch-clamp technique.
The addition of amino acid residues to the N-terminus of the MscL did not affect channel activity, whereas N-terminal deletions
or changes to the N-terminal amino acid sequence were poorly tolerated and resulted in channels exhibiting altered pressure
sensitivity and gating. Deletion of 27 amino acids from the C-terminus resulted in MscL protein that formed channels similar
to the wild-type, while deletion of 33 C-terminal amino acids extinguished channel activity. Similarly, deletion of the internal
amphipathic region of the MscL abolished activity. In accordance with a recently proposed spatial model of the MscL, our results
suggest that (i) the N-terminal portion participates in the channel activation by pressure, and (ii) the essential channel
functions are associated with both, the putative central amphipathic α-helical portion of the protein and the six C-terminal
residues RKKEEP forming a charge cluster following the putative M2 membrane spanning α-helix.
Received: 25 September 1996/Revised: 21 November 1996 相似文献
5.
Yolande Bertin Jean-Pierre Girardeau Maurice Der Vartanian Christine Martin 《FEMS microbiology letters》1993,108(1):59-67
Abstract The putative chaperone-like protein ClpE, required for biogenesis of the Escherichia coli capsule-like antigen CS31A, was compared with ten known periplasmic chaperones from E. coli, Klebsiella pneumoniae, Bordetella pertussis, Haemophilus influenzae and Yersinia pestis . The amino acid sequence alignment was superimposed onto the three-dimensional structure of the PapD chaperone of uropathogenic E. coli , and amino acid residues involved in maintaining the structure integrity of the suggested binding site were found identical in most of the 11 chaperones. Construction of a phylogenetic tree to investigate the relationship within the chaperone family has revealed interesting degrees of relatedness between the different proteins. 相似文献
6.
Glutamine synthetase type I (GSI) genes have previously been described only in prokaryotes except that the fungus Emericella nidulans contains a gene (fluG) which encodes a protein with a large N-terminal domain linked to a C-terminal GSI-like domain. Eukaryotes generally contain
the type II (GSII) genes which have been shown to occur also in some prokaryotes. The question of whether GSI and GSII genes
are orthologues or paralogues remains a point of controversy. In this article we show that GSI-like genes are widespread in
higher plants and have characterized one of the genes from the legume Medicago truncatula. This gene is part of a small gene family and is expressed in many organs of the plant. It encodes a protein similar in size
and with between 36 and 46% amino acid sequence similarity to prokaryotic GS proteins used in the analyses, whereas it is
larger and with less than 25% similarity to GSII proteins, including those from the same plant species. Phylogenetic analyses
suggest that this protein is most similar to putative proteins encoded by expressed sequence tags of other higher plant species
(including dicots and a monocot) and forms a cluster with FluG as the most divergent of the GSI sequences. The discovery of
GSI-like genes in higher plants supports the paralogous evolution of GSI and GSII genes, which has implications for the use
of GS in molecular studies on evolution.
Received: 4 May 1999 / Accepted: 17 September 1999 相似文献
7.
Interactive surface in the PapD chaperone cleft is conserved in pilus chaperone superfamily and essential in subunit recognition and assembly. 总被引:9,自引:0,他引:9 下载免费PDF全文
The assembly of adhesive pili in Gram-negative bacteria is modulated by specialized periplasmic chaperone systems. PapD is the prototype member of the superfamily of periplasmic pilus chaperones. Previously, the alignment of chaperone sequences superimposed on the three dimensional structure of PapD revealed the presence of invariant, conserved and variable amino acids. Representative residues that protruded into the PapD cleft were targeted for site directed mutagenesis to investigate the pilus protein binding site of the chaperone. The ability of PapD to bind to fiber-forming pilus subunit proteins to prevent their participation in misassembly interactions depended on the invariant, solvent-exposed arginine-8 (R8) cleft residue. This residue was also essential for the interaction between PapD and a minor pilus adaptor protein. A mutation in the conserved methionine-172 (M172) cleft residue abolished PapD function when this mutant protein was expressed below a critical threshold level. In contrast, radical changes in the variable residue glutamic acid-167 (E167) had little or no effect on PapD function. These studies provide the first molecular details of how a periplasmic pilus chaperone binds to nascently translocated pilus subunits to guide their assembly into adhesive pili. 相似文献
8.
Christine P. Piotte Airlie K. Hunter Craig J. Marshall Murray R. Grigor 《Journal of molecular evolution》1998,46(3):361-369
Three proteins have been identified in the milk of the common brush tail possum, Trichosurus vulpecula that from sequence analysis are members of the lipocalin family. They include β-lactoglobulin, which appears to have two
forms; a homologue to the late-lactation protein found in tammar, Macropus eugenii; milk; and a novel protein termed trichosurin. Whereas β-lactoglobulin and trichosurin are both expressed throughout lactation, the late-lactation protein is not detected
in samples taken before days 100–110 of lactation. The cDNAs encoding each of these proteins have been isolated from cDNA
libraries prepared using possum mammary mRNA and sequenced. Phylogenetic analysis showed that the T. vulpeculaβ-lactoglobulin, along with two other macropod β-lactoglobulins, forms a subclass of β-lactoglobulins distinct from those
for eutherian mammals; both marsupial late-lactation proteins appear to have similarities to a family of odorant-binding proteins,
whereas trichosurin has similarities to the major urinary proteins of rodents.
Received: 28 October 1996 / Accepted: 19 May 1997 相似文献
9.
Sequence Analyses and Phylogenetic Characterization of the ZIP Family of Metal Ion Transport Proteins 总被引:1,自引:0,他引:1
Several novel but similar heavy metal ion transporters, Zrt1, Zrt2, Zip1-4 and Irt1, have recently been characterized. Zrt1,
Zrt2 and Zip1-4 are probably zinc transporters in Saccharomyces cerevisiae and Arabidopsis thaliana whereas Irt1 appears to play a role in iron uptake in A. thaliana. The family of proteins including these functionally characterized transporters has been designated the Zrt- and Irt-related
protein (ZIP) family. In this report, ZIP family proteins in the current databases were identified and multiply aligned, and
a phylogenetic tree for the family was constructed. A family specific signature sequence was derived, and the available sequences
were analyzed for residues of potential functional significance. A fully conserved intramembranous histidyl residue, present
within a putative amphipathic, α-helical, transmembrane spanning segment, was identified which may serve as a part of an intrachannel
heavy metal ion binding site. The occurrence of a proposed extramembranal metal binding motif (H X H X H) was examined in
order to evaluate its potential functional significance for various members of the family. The computational analyses reported
in this topical review should serve as a guide to future researchers interested in the structure-function relationships of
ZIP family proteins.
Received: 31 March 1997/Revised: 14 May 1998 相似文献
10.
We have isolated a 29,000-Da carbonic anhydrase (CA) protein from the zebrafish, Danio rerio, sequenced two peptide fragments, and tentatively identified it as a high-activity CA by inhibition kinetics. We have also
characterized a 1,537-bp message whose deduced sequence of 260 amino acids matches that of the isolated protein. This CA is
clearly an α-CA based on the similarity of its sequence to that of other members of the α-CA gene family. A phylogenetic analysis
suggested CAH-Z diverged after the branching of the CA-V and CA-VII genes and prior to the duplications that generated the
CA-I, CA-II, and CA-III genes of amniotes. This marks the first characterization of the mRNA and its protein product from
the CA gene of a teleost.
Received: 31 March 1996 / Accepted: 8 September 1996 相似文献
11.
Summary. Phosphate transport in bacteria occurs via a phosphate specific transporter system (PSTS) that belongs to the ABC family of
transporters, a multisubunit system, containing an alkaline phosphatase. DING proteins were characterized due to the N-terminal
amino acid sequence DINGG GATL, which is highly conserved in animal and plant isolates, but more variable in microbes. Most
prokaryotic homologues of the DING proteins often have some structural homology to phosphatases or periplasmic phosphate-binding
proteins. In E. coli, the product of the inducible gene DinG, possesses ATP hydrolyzing helicase enzymic activity. An alkaline phosphorolytic enzyme of the PSTS system was purified
to homogeneity from the thermophilic bacterium Thermus thermophilus. N-terminal sequence analysis of this protein revealed the same high degree of similarity to DING proteins especially to
the human synovial stimulatory protein P205, the steroidogenesis-inducing protein and to the phosphate ABC transporter, periplasmic
phosphate-binding protein, putative (P. fluorescens Pf-5). The enzyme had a molecular mass of 40 kDa on SDS/PAGE, exhibiting optimal phosphatase activity at pH 12.3 and 70 °C.
The enzyme possessed characteristics of a DING protein, such as ATPase, ds endonuclease and 3′ phosphodiesterase (3′-exonuclease)
activities and binding to linear dsDNA, displaying helicase activity on supercoiled DNA. Purification and biochemical characterization
of a T. thermophilus DING protein was achieved. The biochemical properties, N-terminal sequence similarities of this protein implied that the
enzyme belongs to the PSTS family and might be involved in the DNA repair mechanism of this microorganism.
Authors’ address: Assist. Prof. A. A. Pantazaki, Laboratory of Biochemistry, Department of Chemistry, Aristotle University
of Thessaloniki, Thessaloniki 54124, Greece 相似文献
12.
Molecular dissection of PapD interaction with PapG reveals two chaperone-binding sites 总被引:6,自引:2,他引:4
Zheng Xu C. Hal Jones David Haslam Jerome S. Pinkner Karen Dodson Jan Kihlberg Scott J. Hultgren 《Molecular microbiology》1995,16(5):1011-1020
P pili are composite adhesive fibres that allow uropathogenic Escherichia coli to gain a foothold in the host by binding to receptors present on the uroepithalium via the adhesin PapG. The assembly of P pili requires a periplasmic chaperone, PapD, that has an immunoglobulin-like three-dimensional structure. PapD-subunit complex formation involves a conserved anchoring mechanism in the chaperone cleft and a‘molecular zippering’to the extreme C-terminus of pilus subunits. A chaperone-binding assay was developed using fusions of the C-terminus of PapG to maltose-binding protein (MBP/G fusions) to investigate whether chaperone-subunit complex formation requires additional interactions. PapD bound strongly to an MBP/G fusion containing the C-terminal 140 amino acids of PapG (MBP/G175-314) but only weakly to the MBP/G234-314 fusion containing 81 C-terminal residues, arguing that the region between residues 175-234 contains additional information that is required for strong PapD-PapG interactions. PapD was shown to interact with a PapG C-terminal truncate containing residues 1-198 but not a truncate containing residues 1-145, suggesting the presence of a second, independent PapD interactive site. Four peptides overlapping the second site region were tested for binding to PapD in vitro to further delineate this motif. Only one of the peptides synthesized was recognized by PapD. The MBP/G fusion containing both binding sites formed a tight complex with PapD in vivo and inhibited pilus assembly by preventing chaperone-subunit complex formation. 相似文献
13.
The Drosophila fat body protein 2 gene (Fbp2) is an ancient duplication of the alcohol dehydrogenase gene (Adh) which encodes a protein that differs substantially from ADH in its methionine content. In D. melanogaster, there is one methionine in ADH, while there are 51 (20% of all amino acids) in FBP2. Methionine is involved in 46% of amino
acid replacements when Fbp2 DNA sequences are compared between D. melanogaster and D. pseudoobscura. Methionine accumulation does not affect conserved residues of the ADH-ADHr-FBP2 multigene family. The multigene family has evolved by replacement of mildly hydrophobic amino acids by methionine with
no apparent reversion. Its short-term evolution was compared between two Drosophila species, while its long-term evolution was compared between two genera belonging respectively to acalyptrate and calyptrate
Diptera, Drosophila and Sarcophaga. The pattern of nucleotide substitution was consistent with an independent accumulation of methionines at the Fbp2 locus in each lineage. Under a steady-state model, the rate of methionine accumulation was constant in the lineage leading
to Drosophila, and was twice as fast as that in the calyptrate lineage. Substitution rates were consistent with a slight positive selective
advantage for each methionine change in about one-half of amino acid sites in Drosophila. This shows that selection can potentially account for a large proportion of amino acid replacements in the molecular evolution
of proteins.
Received: 12 December 1994 / Accepted: 15 April 1996 相似文献
14.
A Novel Family of Ubiquitous Heavy Metal Ion Transport Proteins 总被引:33,自引:0,他引:33
We describe a novel diverse family of metal ion transporter (CDF) proteins (the cation diffusion facilitator (CDF) family)
with members occurring in both prokaryotes and eukaryotes. Thirteen sequenced protein members of the CDF family have been
identified, several of which have been shown to transport cobalt, cadmium and/or zinc. All members of the CDF family possess
six putative transmembrane spanners with strongest conservation in the four N-terminal spanners, and on the basis of the analyses,
we present a unified structural model. Members of the family are shown to exhibit an unusual degree of size variation, sequence
divergence, and differences in cell localization and polarity. The phylogenetic tree for the CDF family reveals that prokaryotic
and eukaryotic proteins cluster separately. It allows functional predictions for some uncharacterized members of this family.
A signature sequence specific for the CDF family is derived.
Received: 15 July 1996/Revised: 21 October 1996 相似文献
15.
Charles Robin Robyn J. Russell Kerrie M. Medveczky John G. Oakeshott 《Journal of molecular evolution》1996,43(3):241-252
The α-esterase cluster of D. melanogaster contains 11 esterase genes dispersed over 60 kb. Embedded in the cluster are two unrelated open reading frames that have
sequence similarity with genes encoding ubiquitin-conjugating enzyme and tropomyosin. The esterase amino acid sequences show
37–66% identity with one another and all but one have all the motifs characteristic of functional members of the carboxyl/cholinesterase
multigene family. The exception has several frameshift mutations and appears to be a pseudogene. Patterns of amino acid differences
among cluster members in relation to generic models of carboxyl/cholinesterase protein structure are broadly similar to those
among other carboxyl/cholinesterases sequenced to date. However the α-esterases differ from most other members of the family
in: their lack of a signal peptide; the lack of conservation in cysteines involved in disulfide bridges; and in four indels,
two of which occur in or adjacent to regions that align with proposed substrate-binding sites of other carboxyl/cholinesterases.
Phylogenetic analyses clearly identify three simple gene duplication events within the cluster. The most recent event involved
the pseudogene which is located in an intron of another esterase gene. However, relative rate tests suggest that the pseudogene
remained functional after the duplication event and has become inactive relatively recently. The distribution of indels also
suggests a deeper node in the gene phylogeny that separates six genes at the two ends of the cluster from a block of five
in the middle.
Received: 18 January 1996 / Accepted: 12 March 1996 相似文献
16.
Conserved immunoglobulin-like features in a family of periplasmic pilus chaperones in bacteria. 总被引:19,自引:2,他引:17 下载免费PDF全文
Detailed structural analyses revealed a family of periplasmic chaperones in Gram-negative prokaryotes which are structurally and possibly evolutionarily related to the immunoglobulin superfamily and assist in the assembly of adhesive pili. The members of this family have similar structures consistent with the overall topology of an immunoglobulin fold. Seven pilus chaperone sequences from Escherichia coli, Haemophilus influenzae and Klebsiella pneumoniae were aligned and their consensus sequence was superimposed onto the known three-dimensional structure of PapD, a representative member of the family. The molecular details of the conserved and variable structural motifs in this family of periplasmic chaperones give important insight into their structure, function, mechanism of action and evolutionary relationship with the immunoglobulin superfamily. 相似文献
17.
Gerhard Schenk Roy Layfield Judith M. Candy Ronald G. Duggleby Peter F. Nixon 《Journal of molecular evolution》1997,44(5):552-572
Members of the transketolase group of thiamine-diphosphate-dependent enzymes from 17 different organisms including mammals,
yeast, bacteria, and plants have been used for phylogenetic reconstruction. Alignment of the amino acid and DNA sequences
for 21 transketolase enzymes and one putative transketolase reveals a number of highly conserved regions and invariant residues
that are of predicted importance for enzyme activity, based on the crystal structure of yeast transketolase. One particular
sequence of 36 residues has some similarities to the nucleotide-binding motif and we designate it as the transketolase motif.
We report further evidence that the recP protein from Streptococcus pneumoniae might be a transketolase and we list a number of invariant residues which might be involved in substrate binding. Phylogenies
derived from the nucleotide and the amino acid sequences by various methods show a conventional clustering for mammalian,
plant, and gram-negative bacterial transketolases. The branching order of the gram-positive bacteria could not be inferred
reliably. The formaldehyde transketolase (sometimes known as dihydroxyacetone synthase) of the yeast Hansenula polymorpha appears to be orthologous to the mammalian enzymes but paralogous to the other yeast transketolases. The occurrence of more
than one transketolase gene in some organisms is consistent with several gene duplications. The high degree of similarity
in functionally important residues and the fact that the same kinetic mechanism is applicable to all characterized transketolase
enzymes is consistent with the proposition that they are all derived from one common ancestral gene. Transketolase appears
to be an ancient enzyme that has evolved slowly and might serve as a model for a molecular clock, at least within the mammalian
clade.
Received: 13 September 1995 / Accepted: 14 November 1996 相似文献
18.
Evolutionary Relationship of the Ligand-Gated Ion Channels and the Avermectin-Sensitive,Glutamate-Gated Chloride Channels 总被引:4,自引:0,他引:4
Demetrios K. Vassilatis Keith O. Elliston Philip S. Paress Michel Hamelin Joseph P. Arena James M. Schaeffer Lex H.T. Van der Ploeg Doris F. Cully 《Journal of molecular evolution》1997,44(5):501-508
Two cDNAs, GluClα and GluClβ, encoding glutamate-gated chloride channel subunits that represent targets of the avermectin
class of antiparasitic compounds, have recently been cloned from Caenorhabditis elegans (Cully et al., Nature, 371, 707–711, 1994). Expression studies in Xenopus oocytes showed that GluClα and GluClβ have pharmacological profiles distinct from the glutamate-gated cation channels as
well as the γ-aminobutyric acid (GABA)- and glycine-gated chloride channels. Establishing the evolutionary relationship of
related proteins can clarify properties and lead to predictions about their structure and function. We have cloned and determined
the nucleotide sequence of the GluClα and GluClβ genes. In an attempt to understand the evolutionary relationship of these
channels with the members of the ligand-gated ion channel superfamily, we have performed gene structure comparisons and phylogenetic
analyses of their nucleotide and predicted amino acid sequences. Gene structure comparisons reveal the presence of several
intron positions that are not found in the ligand-gated ion channel superfamily, outlining their distinct evolutionary position.
Phylogenetic analyses indicate that GluClα and GluClβ form a monophyletic subbranch in the ligand-gated ion channel superfamily
and are related to vertebrate glycine channels/receptors. Glutamate-gated chloride channels, with electrophysiological properties
similar to GluClα and GluClβ, have been described in insects and crustaceans, suggesting that the glutamate-gated chloride
channel family may be conserved in other invertebrate species. The gene structure and phylogenetic analyses in combination
with the distinct pharmacological properties demonstrate that GluClα and GluClβ belong to a discrete ligand-gated ion channel
family that may represent genes orthologous to the vertebrate glycine channels.
Received: 30 September 1996 / Accepted: 15 November 1996 相似文献
19.
Annexin homologues in the kingdoms of Planta and Protista were characterized by molecular sequence analysis to determine
their phylogenetic and structural relationship with annexins of Animalia. Sequence fragments from 19 plant annexins were identified
in sequence databases and composite sequences were also assembled from expressed sequence tags for Arabidopsis thaliana. Length differences in protein amino-termini and evidence for unique exon splice sites indicated that plant annexins were
distinct from those of animals. A third annexin gene of Giardia lamblia (Anx21-Gla) was identified as a distant relative to other protist annexins and to those of higher eukaryotes, thus providing a suitable
outgroup for evolutionary reconstruction of the family tree. Rooted evolutionary trees portrayed protist, plant, and Dictyostelium annexins as early, monophyletic ramifications prior to the appearance of closely related animal annexin XIII. Molecular phylogenetic
analyses of DNA and protein sequence alignments revealed at least seven separate plant subfamilies, represented by Anx18 (alfalfa, previously classified), Anx22 (thale cress), Anx23 (thale cress, cotton, rape and cabbage), Anx24 (bell pepper and tomato p34), Anx25 (strawberry, horseradish, pea, soybean, and castor bean), Anx26-Zma, and Anx27-Zma (maize). Other unique subfamilies may exist for rice, tomato p35, apple, and celery annexins. Consensus sequences compiled
for each eukaryotic kingdom showed some breakdown of the ``annexin-fold' motif in repeats 2 and 3 of protist and plant annexins
and a conserved codon deletion in repeat 3 of plants. The characterization of distinct annexin genes in plants and protists
reflects their comparable diversity among animal species and offers alternative models for the comparative study of structure–function
relationships within this important gene family.
Received: 30 May 1996 / Accepted: 20 August 1996 相似文献