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Protein
& Peptide Letters
ISSN: 0929-8665
Protein
& Peptide Letters
Volume 16, Number 12, 2009
Contents
Special Board Members Issue
Editorial Pp. 1424
FCS-Based Sensing for the Detection of Ochratoxin
and Neomycin in Food Pp. 1425-1428
Antonio Varriale, Maria Staiano, Luisa Iozzino,
Lorella Severino, Aniello Anastasio, Maria Luisa Cortesi
and Sabato D’Auria
[Abstract] [Purchase
Article]
Identifying Sequences Potentially Related to Resistance
Response of Piper tuberculatum to Fusarium solani
f. sp. piperis by Suppression Subtractive Hybridization
Pp. 1429-1434
Soelange Bezerra Nascimento, Júlio Cezar de Mattos
Cascardo, Ilmarina Campos de Menezes, Maria de Lourdes Reis
Duarte, Sylvain Darnet, Maria Lúcia Harada and
Cláudia Regina Batista de Souza
[Abstract] [Purchase
Article]
Functional Cloning and Expression of
a Novel Endo-α-1,5-L-Arabinanase
from a Metagenomic Library Pp. 1435-1441
Dominic W.S. Wong, Victor J. Chan and Amanda
A. McCormack
[Abstract] [Purchase
Article]
The Small GTPase Activity of the ROC
Domain from LRRK2, a Parkin-son’s Disease Related Protein
Pp. 1442-1446
Qing-Shan Fu, Ai-Xin Song, Su-Xia Li and Hong-Yu
Hu
[Abstract] [Purchase
Article]
Robust Prediction of B-Factor Profile from Sequence
Using Two-Stage SVR Based on Random Forest Feature Selection
Pp. 1447-1454
Xiao-Yong Pan and Hong-Bin Shen
[Abstract] [Purchase
Article]
A Study on the Importance of Phenylalanine
for Aurein Functionality Pp. 1455-1458
Sarah R. Dennison, Frederick Harris and David
A. Phoenix
[Abstract] [Purchase
Article]
Properties of a Kunitz-Type Trypsin Inhibitor
from Delonix regia Seeds Against Digestive Proteinases
of Anagasta kuehniella (Z.) and Corcyra cephalonica
(S.) (Lepidoptera: Pyralidae) Pp. 1459-1465
M.L.R. Macedo, S.C. Pando, L.R. Chevreuil and
S. Marangoni
[Abstract] [Purchase
Article]
N-Heterocyclic Dipeptide Aldehyde Calpain
Inhibitors Pp. 1466-1472
Seth A. Jones, Matthew A. Jones, Stephen B. McNabb,
Steven G. Aitken, James M. Coxon and Andrew D. Abell
[Abstract] [Purchase
Article]
Crystal Structure of Bucain, a Three-Fingered
Toxin from the Venom of the Malayan Krait (Bungarus candidus)
Pp. 1473-1477
M.T. Murakami, R.M. Kini and R.K. Arni
[Abstract] [Purchase
Article]
Gpos-mPLoc: A Top-Down Approach to Improve
the Quality of Predicting Subcellular Localization of Gram-Positive
Bacterial Proteins Pp. 1478-1484
Hong-Bin Shen and Kuo-Chen Chou
[Abstract] [Purchase
Article]
An Investigation of the Molecular Interactions
of Diacetylcurcumin with Ribonuclease A Pp. 1485-1495
Bijaya Ketan Sahoo, Kalyan Sundar Ghoshand Swagata
Dasgupta
[Abstract] [Purchase
Article]
The Dispersion of Water Proton Spin-Lattice Relaxation
Rates in Aqueous Human Protein HC (α1-Microglobulin)
Solutions Pp. 1496-1503
Maria Dobies, Maciej Kozak, Stefan Jurga and Anders
Grubb
[Abstract] [Purchase
Article]
The Production and Role of Gastrin-17 and Gastrin-17-Gly
in Gastrointes-tinal Cancers Pp. 1504-1518
Jeffrey Copps, Richard F. Murphy and Sándor
Lovas
[Abstract] [Purchase
Article]
Insights on the Structure of Amyloid Fibrils
from Site-Directed Muta-genesis Pp. 1519-1525
Daniel Henrique do Amaral Corrêa and Carlos
Henrique Inácio Ramos
[Abstract] [Purchase
Article]
Two Kunitz-Type Inhibitors with Activity Against
Trypsin and Papain from Pithecellobium dumosum Seeds:
Purification, Characterization, and Activity Towards Pest
Insect Digestive Enzyme Pp. 1526-1532
A.S. Oliveira, L. Migliolo, R.O. Aquino, J.K.C. Ribeiro, L.L.P.
Macedo, M.P. Bemquerer, E.A. Santos, S. Kiyota and
M.P. de Sales
[Abstract] [Purchase
Article]
Unfoldomics of Human Genetic Diseases: Illustrative
Examples of Ordered and Intrinsically Disordered Members of
the Human Diseasome Pp. 1533-1547
Uros Midic, Christopher J. Oldfield, A. Keith Dunker, Zoran
Obradovic and Vladimir N. Uversky
[Abstract] [Purchase
Article]
Amyloidogenicity and Aggregate Cytotoxicity of Human
Glucagon-Like Peptide-1 (hGLP-1) Pp. 1548-1556
S. Poon, N.R. Birkett, S.B. Fowler, B.F. Luisi, C.M. Dobson
and J. Zurdo
[Abstract] [Purchase
Article]
Characterization of a Saccharide-Binding Protein from
Talisia esculenta Seeds with Trypsin Inhibitory Activity
Pp. 1557-1564
Maria das Graças M. Freire, Ilka Maria Vasconcelos,
Marcos Vinícius Oliveira, Gonçalo Apolinário
de Souza Filho and Maria Lígia R. Macedo
[Abstract] [Purchase
Article]
Abstracts
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Editorial:
This issue of Protein and Peptide Letters is the
second one in which all the manuscripts have been contributed
by members of the Editorial Advisory Board, following an earlier
issue last year (Vol. 15 No. 9, 2008). The papers
included here demonstrate the wide variety of research areas
covered by the Editorial Board. The field of proteins and
peptides is very broad, encompassing wide areas of current
chemistry, biology, biomaterials and related areas. This is
true, of course, because protein and peptides can be found
in all living systems and are responsible for both form and
function, i.e., structural proteins and enzymes, to name just
two examples. The accelerating discoveries of the roles of
these molecules in the pathology of diseases and in new biomaterials
with useful properties promise to expand the field even further.
Now that we have expanded the publication of Protein &
Peptide Letters to 12 issues per year, we plan to continue
scheduling the December issue each year for papers submitted
by Editorial Advisory Board members. Each manuscript is submitted
to the Editor-in-Chief and subjected to the same peer review
process as all other submissions to the journal. We invite
our EABMs to begin planning for submission of their best work
for the December 2010 issue.
It is also a pleasure to announce that the Content Management
System for online submission of abstracts and manuscript is
now fully functional. All authors are invited to access the
system at http://www.bentham-editorial.org to register and
submit your documents. Follow the online prompts to establish
a username and password and then you can access your manuscript
and read comments from the referees.
Ben M. Dunn
Editor-in-Chief, Protein & Peptide Letters
Biochemistry and Molecular Biology
University of Florida, College of Medicine
Gainesville, FL 32610-0245
USA
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[Purchase Article]
FCS-Based Sensing for the Detection of Ochratoxin
and Neomycin in Food
Antonio Varriale, Maria Staiano, Luisa Iozzino,
Lorella Severino, Aniello Anastasio, Maria Luisa Cortesi
and Sabato D’Auria
In this work, we present an advanced fluorescence assay
for the detection of traces of ocratoxin A and neomycin in
food. The described assay is based on measurement of the fluctuations
of the fluorescein-labeled analytes by a focused laser beam
in the absence and in the presence of the specific antibodies
anti-analytes. A competitive assay based on the utilization
of unlabeled analytes was developed. The obtained results
indicated that the combination of high-avidity IgG antibodies
together with an innovative fluorescence immunoassay strategy
resulted in the detection limit of 0.0078 ng and 0.0156 ng
for ochratoxin A and neomycin, respectively.
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[Purchase
Article]
Identifying Sequences Potentially Related to Resistance
Response of Piper tuberculatum to Fusarium solani
f. sp. piperis by Suppression Subtractive Hybridization
Soelange Bezerra Nascimento, Júlio Cezar de Mattos
Cascardo, Ilmarina Campos de Menezes, Maria de Lourdes Reis
Duarte, Sylvain Darnet, Maria Lúcia Harada and
Cláudia Regina Batista de Souza
Piper tuberculatum is an exotic Piper from the
Amazon region that shows resistance to infection by Fusarium
solani f. sp. piperis, causal agent of Fusarium
disease in black pepper (Piper nigrum L.). In
this work we aimed to study the interaction between P.
tuberculatum and F. solani f. sp. piperis at
a molecular level, using suppression subtractive hybridization
to identify genes potentially related to Fusarium
disease resistance. Comparative sequence analysis confirmed
that clones isolated here show a high identity with genes
coding for proteins that have a known role in plant defense
response mechanisms, such as peroxidase, hydroxyproline-rich
glycoprotein and CBL-interacting protein kinase. The present
study constitutes the first effort to understand the molecular
basis of this plant-pathogen interaction, identifying genes
which may be used in the future genetic improvement of black
pepper.
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Article]
Functional Cloning and Expression of
a Novel Endo-α-1,5-L-Arabinanase
from a Metagenomic Library
Dominic W.S. Wong, Victor J. Chan and Amanda
A. McCormack
A novel endo-α-L-arabinanase
gene (arn2) was isolated, and expressed in E.
coli in active form. The recombinant enzyme (ARN2) had
optimum activity at pH 6.0 and 45-50°C with stability
between pH 5.0-8.0 and at temperatures up to 40°C. The
recombinant ARN2 catalyzed internal cleavage of α-1,5
glycosidic bonds of CM-arabinan, debranched arabinan, linear
arabinan, and sugar beet (native) arabinan at rates of decreasing
order, and was inactive on wheat arabinoxylan and p-nitrophenyl-α-L-arabinofuranoside.
Kinetic analysis showed that branching in the arabinan did
not significantly affect the apparent Km
values, and the difference in the reaction rates was likely
due to the chemical step after substrate binding. The enzyme
hydrolyzed arabino-oligosaccharides of DP≥6 to smaller
oligomers and mostly arabinotriose. Natural and modified arabinans
were cleaved to oligomers of various chain lengths, which
were progressively hydrolyzed to yield arabinotriose. The
pattern of degradation revealed an endo-acting mechanism with
arabinotriose as the end product.
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[Purchase Article]
The Small GTPase Activity of the ROC
Domain from LRRK2, a Parkin-son’s Disease Related Protein
Qing-Shan Fu, Ai-Xin Song, Su-Xia Li and Hong-Yu
Hu
Mutations in the LRRK2 gene have been implicated in the
pathogenesis of Parkinson’s disease. This work provides
biochemical evidence that the ROC domain of LRRK2 functions
as a small GTPase, and the Parkinson’s disease-associated
mutants do not appear to have reduced GTP hydrolysis activities.
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[Purchase Article]
Robust Prediction of B-Factor Profile from Sequence
Using Two-Stage SVR Based on Random Forest Feature Selection
Xiao-Yong Pan and Hong-Bin Shen
B-factor is highly correlated with protein internal motion,
which is used to measure the uncertainty in the position of
an atom within a crystal structure. Although the rapid progress
of structural biology in recent years makes more accurate
protein structures available than ever, with the avalanche
of new protein sequences emerging during the post-genomic
Era, the gap between the known protein sequences and the known
protein structures becomes wider and wider. It is urgent to
develop automated methods to predict B-factor profile from
the amino acid sequences directly, so as to be able to timely
utilize them for basic research. In this article, we propose
a novel approach, called PredBF, to predict the real value
of B-factor. We firstly extract both global and local features
from the protein sequences as well as their evolution information,
then the random forests feature selection is applied to rank
their importance and the most important features are inputted
to a two-stage support vector regression (SVR) for prediction,
where the initial predicted outputs from the 1st
SVR are further inputted to the 2nd
layer SVR for final refinement. Our results have revealed
that a systematic analysis of the importance of different
features makes us have deep insights into the different contributions
of features and is very necessary for developing effective
B-factor prediction tools. The two-layer SVR prediction model
designed in this study further enhanced the robustness of
predicting the B-factor profile. As a web server, PredBF is
freely available at: http://www.csbio.sjtu.edu.cn/bioinf/PredBF
for academic use.
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[Purchase Article]
A Study on the Importance of Phenylalanine
for Aurein Functionality Pp. 1455-1458
Sarah R. Dennison, Frederick Harris and David
A. Phoenix
Aurein 2.5 (GLFDIVKKVVGAFGSL-NH2)
is an amphibian antimicrobial peptide. Here, characterisation
studies showed the peptide to exhibit molecular areas at an
air / water interface (1.77 – 3.1 nm2),
which are in agreement with the adoption of α-helical
structures. Lipid monolayer studies showed aurein 2.5 to induce
maximal surface pressure changes of circa 7 mN m-1
in monolayers formed from phosphatidylglycerol (PG) and circa
6 mN m-1 in those formed
from phosphatidylethanolamine (PE). These data indicate that
the membrane interactions of the peptide are amphiphilicity
driven with no apparent electrostatic requirement. Individually
mutating the phenylalanine residues of aurein 2.5 to leucine
had no major effect on the levels of PG and PE interactions,
suggesting that these residues are not essential to the membrane
interactions of the peptide, contrasting to other aureins
where corresponding phenylalanine residues are required for
efficient membrane interaction and antibacterial activity.
This difference in the requirement is suggested to relate
to the surface architecture as proposed by the concept of
the molecular perturbation potential.
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[Purchase
Article]
Properties of a Kunitz-Type Trypsin Inhibitor
from Delonix regia Seeds Against Digestive Proteinases
of Anagasta kuehniella (Z.) and Corcyra cephalonica
(S.) (Lepidoptera: Pyralidae)
M.L.R. Macedo, S.C. Pando, L.R. Chevreuil and
S. Marangoni
DrTI was effective against trypsin-like enzymes from
A. kuehniella and C. cephalonica, however
an artificial diet was insufficient to affect the survival
and body weight of either insect. The inhibitor stimulated
chymotrypsin-like enzymes and probably induced the synthesis
of enzymes insensitive to TLCK in neonate larvae.
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[Purchase Article]
N-Heterocyclic Dipeptide Aldehyde Calpain
Inhibitors
Seth A. Jones, Matthew A. Jones, Stephen B. McNabb,
Steven G. Aitken, James M. Coxon and Andrew D. Abell
A series of Val-Leu based peptidic aldehydes containing either
a furan or thiophene at the N-terminus was prepared and assayed
against ovine m-calpain. In general, potency is favoured by
a 2-substituted (rather than 3-substituted) heterocycle, a
thiophene rather than a furan, and a shorter chain length
at the N-terminus. Molecular docking experiments provide some
rationale for these observations.
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Article]
Crystal Structure of Bucain, a Three-Fingered
Toxin from the Venom of the Malayan Krait (Bungarus candidus)
M.T. Murakami, R.M. Kini and R.K. Arni
Bucain, a potent neurotoxin isolated from the venom of
the Malayan krait (Bungarus candidus), induces paralysis
and death. Its crystal structure has been determined at 2.10
Å resolution and based on the molecular topology and
hydrophobicity profile is structurally classified as a three-fingered
α-neurotoxin
possessing a positively charged AChR-binding site.
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Article]
Gpos-mPLoc: A Top-Down Approach to Improve
the Quality of Predicting Subcellular Localization of Gram-Positive
Bacterial Proteins
Hong-Bin Shen and Kuo-Chen Chou
In this paper, a new predictor called “Gpos-mPLoc”,
is developed for identifying the subcellular localization
of Gram positive bacterial proteins by fusing the information
of gene ontology, as well as the functional domain information
and sequential evolution information. Compared with the old
Gpos-PLoc, the new predictor is much more powerful and flexible.
Particularly, it also has the capacity to deal with multiple-location
proteins as indicated by the character “m” in
front of “PLoc” of its name. For a newly-constructed
stringent benchmark dataset in which none of included proteins
has ≥ 25% pairwise sequence identity to any other in
a same subset (location), the overall jackknife success rate
achieved by Gpos-mPLoc was 82.2%, which was about 10% higher
than the corresponding rate by the Gpos-PLoc. As a user friendly
web-server, Gpos-mPLoc is freely accessible at http://www.csbio.sjtu.edu.cn/bioinf/Gpos-multi/.
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[Purchase Article]
An Investigation of the Molecular Interactions
of Diacetylcurcumin with Ribonuclease A
Bijaya Ketan Sahoo, Kalyan Sundar Ghoshand Swagata
Dasgupta
Curcumin is a natural product with diverse pharmacological
activities. Studies of curcumin and its structural derivatives
have been a subject of growing interest as a result of their
diverse biological activities. We report the interaction of
diacetylcurcumin (DAC) with Ribonuclease A (RNase A). The
binding constant of DAC with RNase A was found to be of the
order of 104 M-1.
The intrinsic fluorescence of RNase A was quenched by DAC
with a quenching constant of 2.2 ×104
M-1. The distance between
the fluorophore of RNase A and DAC was found to be 2.6 nm,
calculated from a Förster type fluorescence resonance
energy transfer (FRET). Secondary structural changes of RNase
A after binding were analyzed from circular dichroism and
Fourier transform infrared studies. Protein-ligand docking
studies were conducted to determine the residues involved
in the interaction of RNase A with DAC and changes in the
accessible surface of the in-teracting residues were calculated
accordingly.
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The Dispersion of Water Proton Spin-Lattice Relaxation
Rates in Aqueous Human Protein HC (α1-Microglobulin)
Solutions
Maria Dobies, Maciej Kozak, Stefan Jurga and Anders
Grubb
The 1H NMR Fast Field
Cycling relaxometry was applied to study the molecular dynamics
of the human protein HC (α1-microglobulin),
its hydration and aggregation in solution state. The 1H
NMRD data have revealed the complex nature of the water/protein
HC system resulting from the co-existence of monomer and dimer
forms of the protein in solution as well as the presence of
oligosaccharides linked to the polypeptide chain. A comparison
of the average correlation time values <τc>
obtained from the model-free fits with the values predicted
on the basis of hydrodynamic τr
theory, suggests that the dynamics in solution state is governed
mainly by the dimer form of the protein HC (the dominant contribution
to the water proton-spin lattice relaxation comes from exchanging
protons from the surface of the dimer). The existence of small
number of oligomeric forms of the protein HC in solutions
is postulated because of the two-step shape of water proton
spin-lattice relaxation rate dispersion profiles.
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The Production and Role of Gastrin-17 and Gastrin-17-Gly
in Gastrointes-tinal Cancers
Jeffrey Copps, Richard F. Murphy and Sándor
Lovas
The gastrointestinal peptide hormone gastrin is responsible
for initiating the release of gastric acid in the stomach
in response to the presence of food and/or humoral factors
such as gastrin releasing peptide. However, it has a role
in the growth and maintenance of the gastric epithelium, and
has been implicated in the formation and growth of gastric
cancers. Hypergastrinemia resulting from atrophic gastritis
and pernicious anemia leads to hyperplasia and carcinoid formation
in rats, and contributes to tumor formation in humans. Additionally,
gastrin has been suspected to play a role in the formation
and growth of cancers of the colon, but recent studies have
instead implicated gastrin processing intermediates, such
as gastrin-17-Gly, acting upon a putative, non-cholecystokinin
receptor. This review summarizes the production and chemical
structures of gastrin and of the processing intermediate gastrin-17-Gly,
as well as their activities in the gastrointestinal tract,
particularly the promotion of colon cancers.
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Article]
Insights on the Structure of Amyloid Fibrils
from Site-Directed Muta-genesis
Daniel Henrique do Amaral Corrêa and Carlos
Henrique Inácio Ramos
To test the hypothesis that the ability to form ordered
β-rich
amyloid fibers with identical structures is a generic property
of proteins we present a study on the overall structures of
fibers formed by apomyoglobin mutants that either stabilize
or destabilize the native state or the intermediate. Our results
indicate that, at least at the macroscopic level, ordered
β-rich
amyloid fibers have similar structures.
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Two Kunitz-Type Inhibitors with Activity Against
Trypsin and Papain from Pithecellobium dumosum Seeds:
Purification, Characterization, and Activity Towards Pest
Insect Digestive Enzyme
A.S. Oliveira, L. Migliolo, R.O. Aquino, J.K.C. Ribeiro, L.L.P.
Macedo, M.P. Bemquerer, E.A. Santos, S. Kiyota and
M.P. de Sales
Two trypsin inhibitors (called PdKI-3.1 and PdKI-3.2) were
purified from the seeds of the Pithecellobium dumosum
tree. Inhibitors were obtained by TCA precipitation,
affinity chromatography on Trypsin-Sepharose and reversed-phase-HPLC.
SDS-PAGE analysis with or without reducing agent showed that
they are a single polypeptide chain, and MALDI-TOF analysis
determined molecular masses of 19696.96 and 19696.36 Da, respectively.
The N-terminal sequence of both inhibitors showed strong identity
to the Kunitz family trypsin inhibitors. They were stable
over a wide pH (2-9) and temperature (37 to 100 °C)
range. These inhibitors reduced over 84% of trypsin activity
with inhibition constant (Ki) of 4.20 x 10-8
and 2.88 x 10-8 M, and also
moderately inhibited papain activity, a cysteine proteinase.
PdKI-3.1 and PdKI-3.2 mainly inhibited digestive enzymes from
Plodia interpunctella, Zabrotes subfasciatus and
Ceratitis capitata guts. Results show that both inhibitors
are members of the Kunitz-inhibitor family and that they affect
the digestive enzyme larvae of diverse orders, indicating
a potential insect antifeedant.
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Unfoldomics of Human Genetic Diseases: Illustrative
Examples of Ordered and Intrinsically Disordered Members of
the Human Diseasome
Uros Midic, Christopher J. Oldfield, A. Keith Dunker, Zoran
Obradovic and Vladimir N. Uversky
Intrinsically disordered proteins (IDPs) constitute a recently
recognized realm of atypical biologically active proteins
that lack stable structure under physiological conditions,
but are commonly involved in such crucial cellular processes
as regulation, recognition, signaling and control. IDPs are
very common among proteins associated with various diseases.
Recently, we performed a systematic bioinformatics analysis
of the human diseasome, a network that linked the human disease
phenome (which includes all the human genetic diseases) with
the human disease genome (which contains all the disease-related
genes) (Goh, K. I., Cusick, M. E., Valle, D., Childs, B.,
Vidal, M., and Barabasi, A. L. (2007). The human disease network.
Proc. Natl. Acad. Sci. U.S.A. 104, 8685-90). The analysis
of this diseasome revealed that IDPs are abundant in proteins
linked to human genetic diseases, and that different genetic
disease classes varied dramatically in the IDP content (Midic
U., Oldfield C.J., Dunker A.K., Obradovic Z., Uversky V.N.
(2009) Protein disorder in the human diseasome: Unfoldomics
of human genetic diseases. BMC Genomics. In press).
Furthermore, many of the genetic disease-related proteins
were shown to contain at least one molecular recognition feature,
which is a relatively short loosely structured protein region
within a mostly disordered segment with the feature gaining
structure upon binding to a partner. Finally, alternative
splicing was shown to be abundant among the diseasome genes.
Based on these observations the human-genetic-disease-associated
unfoldome was created. This minireview describes several illustrative
examples of ordered and intrinsically disordered members of
the human diseasome.
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Amyloidogenicity and Aggregate Cytotoxicity of Human
Glucagon-Like Peptide-1 (hGLP-1)
S. Poon, N.R. Birkett, S.B. Fowler, B.F. Luisi, C.M. Dobson
and J. Zurdo
The potential of human glucagon-like peptide-1 (hGLP-1)
as a therapeutic agent is limited by its high aggregation
propensity. We show that hGLP-1 forms amyloid-like
structures that are preceded by cytotoxic aggregates, suggesting
that aggregation of biopharmaceuticals could present a cytotoxic
risk to patients besides the reported increased risk in immunogenicity.
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Characterization of a Saccharide-Binding Protein from
Talisia esculenta Seeds with Trypsin Inhibitory Activity
Maria das Graças M. Freire, Ilka Maria Vasconcelos,
Marcos Vinícius Oliveira, Gonçalo Apolinário
de Souza Filho and Maria Lígia R. Macedo
Some proteins exhibit characteristics that suggest they have
a primary, if not an exclusive role in nutrient reserve storage.
The best studied examples are the storage proteins that accumulate
specifically in developing seeds. Some of these protein demonstrate
biological activities that could contribute to resistance
to pest, pathogens or abiotic stresses. In this study we present
the biochemical characterization and cloning of the major
protein from seeds of T. esculenta (Talisin), a member
of the Sapindaceae family. The N-terminal sequence of the
protein isolated was used to produce a degenerated primer.
This primer allowed the amplification of the Talisin cDNA
by RTPCR from mRNA of the T. esculenta seeds protein.
The sequence analysis of the cloned cDNA, demonstrated a 756
bp sequence encoding a peptide of 198 amino acids. The deduced
peptide presented high similarity to a typical VSP, the 22-kDa
protein in lychee (73 %) and 50.0 % identity to Theobroma
bicolor reserve protein. Identities of 52.0 % and 44.0
% to trypsin inhibitors from Treobroma mammosum and
Populus tremula respectively. In conclusion, we may
suggest that Talisin could be a seed storage protein with
affinity properties, i.e. interacts with carbohydrates and
trypsin enzyme.
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