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Protein
& Peptide Letters
ISSN: 0929-8665
Protein &
Peptide Letters
Volume 17, Number 4, 2010
Contents
Regular Papers
A Designed β-Hairpin
Forming Peptide Undergoes a Consecutive Stepwise
Process for Self-Assembly into Nanofibrils Pp.
410-415
C. Wang and Y. Sha
[Abstract] [Purchase
Article] [PMID:
19508190 PubMed - indexed for MEDLINE]
Furin Cleavage of Bacterial Expressed Glutathione-S-Transferase-Pro-
Transforming Growth Factor β1
Fusion Protein In Vitro Pp. 416-418
N.A. Kahle, C. Joffroy, S.L. Popp, C. Knabbe and
M.B. Stope
[Abstract] [Purchase
Article] [PMID:
19594430 PubMed - indexed for MEDLINE]
Dynamic Kinetic Resolution of N-Benzoyl-DL-Amino
Acids via Peptide Bond Forming Reactions Pp. 419-422
T. Miyazawa and T. Hamada
[Abstract] [Purchase
Article] [PMID:
19508192 PubMed - indexed for MEDLINE]
SVMCRYS: An SVM Approach for the Prediction of Protein
Crystallization Propensity from Protein Sequence
Pp. 423-430
K.K. Kandaswamy, G. Pugalenthi, P.N. Suganthan and
R. Gangal
[Abstract] [Purchase
Article] [PMID:
20044918 PubMed - indexed for MEDLINE]
Fluorescent Analogues of the Insect Neuropeptide
Helicokinin I: Synthesis, Photophysical Characterization and
Biological Activity Pp. 431-436
H. Chen, J. Scherkenbeck, T. Zdobinsky and H.
Antonicek
[Abstract] [Purchase
Article] [PMID:
19995343 PubMed - indexed for MEDLINE]
Insight into the Stereospecificity of Short-Chain
Thermus thermophilus Alcohol Dehydrogenase Showing
pro-S Hydride Transfer and Prelog Enantioselectivity
Pp. 437-443
A. Pennacchio, A. Giordano, L. Esposito, E. Langella,
M. Rossi and C.A. Raia
[Abstract] [Purchase
Article]
One-Step Purification of Functional Light-Harvesting
2 Complex from Rhodobacter sphaeroides Pp.
444-448
Z. Zhao, Z. Hu, Y. Liang, T. Hu, Y. Tu and G.
Chen
[Abstract] [Purchase
Article] [PMID:
20015026 PubMed - indexed for MEDLINE]
Primary Structural Documentation of the Major Urinary
Protein of the Indian Commensal Rat (Rattus rattus)
Using a Proteomics Platform Pp. 449-457
R. Rajkumar, S. Prakash, G. Archunan and R. Sowdhamini
[Abstract] [Purchase
Article] [PMID:
20015025 PubMed - indexed for MEDLINE]
Drastic Effects on Fibril Formation of Amyloid-β
Peptides by the Addition of Amino Acid Residue Units to the
Termini Pp. 458-463
Y. Asanomi, Y. Kobayashi, H. Sakai, T. Masuda, X. Chen,
Y. Chuman, K. Uosaki and K. Sakaguchi
[Abstract] [Purchase
Article] [PMID:
20044924 PubMed - indexed for MEDLINE]
Prediction of Protein Subcellular Locations with
Feature Selection and Analysis Pp. 464-472
Y. Cai, J. He, X. Li, K. Feng, L. Lu, K. Feng, X. Kong
and W. Lu
[Abstract] [Purchase
Article] [PMID:
19995336 PubMed - indexed for MEDLINE]
Band Assignment in Hemoglobin Porphyrin Ring Spectrum:
Using Four-Orbital Model of Gouterman Pp. 473-479
M.R. Dayer, A.A. Moosavi-Movahedi and M.S. Dayer
[Abstract] [Purchase
Article] [PMID:
19758117 PubMed - indexed for MEDLINE]
Herbivore Response in Passion Fruit (Passiflora
edulis Sims) Plants: Induction of Lipoxygenase Activity
in Leaf Tissue in Response to Generalist and Specialist Insect
Attack Pp. 480-484
B.C. Jardim, V.A. Perdízio, M.A. Berbert-Molina,
D.C. Rodrigues, S. Botelho-Júnior, A.C.P. Vicente,
E. Hansen, K. Otsuki, T.P. Ürményi and
T. Jacinto
[Abstract] [Purchase
Article] [PMID:
19995344 PubMed - indexed for MEDLINE]
Characterization of an mDock5-Specific Antibody and Tissue-Specific
Expression and Subcellular Localization of mDock5
Pp. 485-491
E. Kim, J.-B. Yoon and S.K. Yoon
[Abstract] [Purchase
Article] [PMID:
19995334 PubMed - indexed for MEDLINE]
Human Hsp70/Hsp90 Organizing Protein (Hop) D456G Is
a Mixture of Monomeric and Dimeric Species Pp. 492-498
D.C. Gonçalves, L.M. Gava and C.H.I. Ramos
[Abstract] [Purchase
Article] [PMID:
19961430 PubMed - indexed for MEDLINE]
Click Chemistry Aided Synthesis of 1,4-Substituted
1,2,3-Triazole Based N-Fmoc Protected ε-Amino
Acids: Isolation, Characterization and Synthesis of Novel
Triazole Based Unnatural Amino Acids Pp. 499-506
V.V. Sureshbabu, N. Narendra, H.P. Hemantha and
G. Chennakrishnareddy
[Abstract] [Purchase
Article] [PMID:
19961431 PubMed - indexed for MEDLINE]
Identifying the Hierarchy of Dynamic
Domains in Proteins Using the Data of Molecular Dynamics Simulations
Pp. 507-516
S.O. Yesylevskyy
[Abstract] [Purchase
Article] [PMID:
20044922 PubMed - indexed for MEDLINE]
Bactericidal and Hemolytic Activities of Synthetic
Peptides Derived from Granulysin Pp. 517-521
A. Siano, G. Tonarelli, M.S. Imaz, J.C. Perín,
N. Ruggeri, M. López ,M.N. Santi and E. Zerbini
[Abstract] [Purchase
Article] [PMID:
19961432 PubMed - indexed for MEDLINE]
Antifungal Activity of Storage 2S Albumins from Seeds
of the Invasive Weed Dandelion Taraxacum officinale
Wigg. Pp. 522-529
T.I. Odintsova, E.A. Rogozhin, I.V. Sklyar , A.K. Musolyamov,
A.M. Kudryavtsev, V.A. Pukhalsky , A.N. Smirnov, E.V. Grishin
and T.A. Egorov
[Abstract] [Purchase
Article] [PMID:
19594427 PubMed - indexed for MEDLINE]
Fitting Evolution of Matrix Protein 1 from Influenza
A Virus Using Analytical Solution of System of Differential
Equations Pp. 530-541
S. Yan, Z. Li and G. Wu
[Abstract] [Purchase
Article] [PMID:
19961428 PubMed - indexed for MEDLINE]
Isolation and Characterization of a Novel Small Antifungal
Peptide from Bacillus megaterium D4 Ísolated
from the Dung of Wild Plateau Yak in China Pp. 542-546
L. Chen and W. Chen
[Abstract] [Purchase
Article] [PMID:
19594429 PubMed - indexed for MEDLINE]
Abstracts
[Back to top] [Purchase
Article] [PMID:
19508190 PubMed - indexed for MEDLINE]
A Designed β-Hairpin
Forming Peptide Undergoes a Consecutive Stepwise
Process for Self-Assembly into Nanofibrils
C. Wang and Y. Sha
We used a de novo designed, β-hairpin
forming T1 peptide as a model to investigate the kinetics
of peptide fibrogenesis by a combination of light scattering
(LS), circular dichroism (CD), fluorescence, and atomic force
microscopy (AFM). The results demonstrate that the T1 fibrogenesis
undergoes a consecutive stepwise process, with a high degree
of cooperation, presenting sigmoidal time-courses of the peptide
aggregation, the subsequent conformational conversion of the
backbone, and the peptide sidechains’ rearrangement.
We suggest that the conformational conversion was initiated
after the peptide aggregates reach a dimensional size threshold,
which could be a key step in the formation of β-structural
nuclei that catalyze the subsequent reactions. Furthermore,
besides triggering the peptide aggregation, the interactions
between the peptide sidechains predominately facilitate the
regular alignment of the peptide molecules and the formation
of a well-defined suprastructure. This work provides an insight
of the hierarchical self-assembly of β-hairpin
forming peptides. It is helpful for designing β-structural
peptides for self-assembly into nanowires, which would have
potential applications in the construction of nano-materials.
[Back to top]
[Purchase
Article]
[PMID:
19594430 PubMed - indexed for MEDLINE]
Furin Cleavage of Bacterial Expressed Glutathione-S-Transferase-Pro-
Transforming Growth Factor β1
Fusion Protein In Vitro
N.A. Kahle, C. Joffroy, S.L. Popp, C. Knabbe and
M.B. Stope
To investigate the processing of transforming growth factor
β1
(TGFβ1)
pro-protein by furin protease we expressed a GST-pro-TGFβ1
fusion protein in bacteria. Analysis of the furin digestion
pattern revealed the liberation of 12.5 kDa TGFβ1
monomers. There was no evidence for cleavage of an alternative
furin site within the pro-protein.
[Back to top]
[Purchase
Article]
[PMID:
19508192 PubMed - indexed for MEDLINE]
Dynamic Kinetic Resolution of N-Benzoyl-DL-Amino
Acids via Peptide Bond Forming Reactions
T. Miyazawa and T. Hamada
Dynamic kinetic resolution (DKR) was demonstrated in the carbodiimide-mediated
couplings of N-benzoyl-DL-amino acids with L-amino
acid esters: the yields of the D-L-peptides significantly
exceeded 50% in some cases. N-Benzoyl-DL-t-leucine
afforded the D-L-peptide almost exclusively (up to 96% yield)
in the reaction with methyl L-prolinate, which is the most
efficient DKR obtained in the field of amino acids and derivatives.
[Back to top]
[Purchase
Article] [PMID:
20044918 PubMed - indexed for MEDLINE]
SVMCRYS: An SVM Approach for the Prediction of Protein
Crystallization Propensity from Protein Sequence
K.K. Kandaswamy, G. Pugalenthi, P.N. Suganthan and
R. Gangal
X-ray crystallography is the most widely used method for protein
3-dimensional structure determination. Selection of target
protein that can yield high quality crystal for X-ray crystallography
is a challenging task. Prediction of protein crystallization
propensity from sequence information is useful for the selection
of target protein for crystallization. Recently, support vector
machines have been widely used to solve various biological
problems. In this work, we present a SVMCRYS method which
use support vector machine to classify protein sequence into
‘amenable to crystallization’ and ‘resistant
to crystallization’. SVMCRYS was trained on a dataset
containing 728 sequences that gave diffraction quality crystal
and 728 sequences where work had been stopped before obtaining
crystal. The performance of SVMCRYS method was compared with
other sequence-based crystallization prediction methods such
as SECRET, CRYSTALP, OB-Score, ParCrys and XtalPred using
three different datasets. SVMCRYS achieved better prediction
rate with higher sensitivity and specificity. Our analysis
suggests that SVMCRYS can be used to predict proteins which
are amenable to crystallization and proteins which are difficult
for crystallization. The SVMCRYS software, dataset and feature
set can be obtained from http://www3.ntu.edu.sg/home/EPNSugan/index_files/svmcrys.htm.
[Back to top]
[Purchase
Article] [PMID:
19995343 PubMed - indexed for MEDLINE]
Fluorescent Analogues of the Insect Neuropeptide
Helicokinin I: Synthesis, Photophysical Characterization and
Biological Activity
H. Chen, J. Scherkenbeck, T. Zdobinsky and H.
Antonicek
In insects numerous physiological processes are regulated
by neuropeptides. Two fluorescent analogues of the amino acids
tryptophan and tyrosine were synthesized and incorporated
in the diuretic neuropeptide helicokinin I from the moth Heliothis
zea. By fluorescence emission measurements it was shown
that both fluorescent helicokinin I analogues react sensitive
on the dielectricity of their microenvironment. A helicokinin
I analogue containing the fluorescent tryptophan mimic β-[6’-(N,N-dimethyl)-amino-2’-naphthoyl]alanine
(Ald) was shown to bind to dodecylphosphocholine (DPC) micelles
by the Ald residue. A membrane binding model for helicokinin
I is proposed based on data from related mammalian and insect-neuropeptides.
[Back to top]
[Purchase
Article]
Insight into the Stereospecificity of Short-Chain
Thermus thermophilus Alcohol Dehydrogenase Showing
pro-S Hydride Transfer and Prelog Enantioselectivity
A. Pennacchio, A. Giordano, L. Esposito, E. Langella,
M. Rossi and C.A. Raia
The stereochemistry of the hydride transfer in reactions catalyzed
by NAD(H)-dependent alcohol dehydrogenase from Thermus
thermophilus HB27 was determined by means of 1H-NMR
spectroscopy. The enzyme transfers the pro-S
hydrogen of [4R-2H]NADH
and exhibits Prelog specificity. Enzyme-substrate docking
calculations provided structural details about the enantioselectivity
of this thermophilic enzyme. These results give additional
insights into the diverse active site architectures of the
largely versatile short-chain dehydrogenase superfamily enzymes.
A feasible protocol for the synthesis of [4R-2H]NADH
with high yield was also set up by enzymatic oxidation of
2-propanol-d8 catalyzed by
Bacillus stearothermophilus alcohol dehydrogenase.
[Back to top]
[Purchase
Article] [PMID:
20015026 PubMed - indexed for MEDLINE]
One-Step Purification of Functional Light-Harvesting
2 Complex from Rhodobacter sphaeroides
Z. Zhao, Z. Hu, Y. Liang, T. Hu, Y. Tu and G.
Chen
Most common methods for isolation of the light-harvesting
2 (LH2) complex are time-consuming. In our present work, functional
LH2 complex was one-step purified from Rhodobacter sphaeroides
by immobilized metal-ion affinity chromatography. The purified
LH2 complex exhibited high activity in light absorption and
energy transfer. Our present work provides an efficient approach
for preparation of functional LH2 complex.
[Back to top]
[Purchase
Article] [PMID:
20015025 PubMed - indexed for MEDLINE]
Primary Structural Documentation of the Major Urinary
Protein of the Indian Commensal Rat (Rattus rattus)
Using a Proteomics Platform
R. Rajkumar, S. Prakash, G. Archunan and R. Sowdhamini
Purpose: A number of proteome studies have
been performed recently to identify pheromone-related protein
expression and their molecular function using genetically
modified rodents’ urine. However, no such studies have
used Indian commensal rodents; interestingly, in a previous
investigation, we confirmed the presence of volatile molecules
in commensal rodents urine and these molecules seem to be
actively involved in pheromonal communication. Therefore,
the present study aims to identify the major urinary protein
[MUP] present in commensal rat urine, which will help us to
understand the protein’s expression pattern and intrinsic
properties among the rodents globally.
Experimental Design: Initially, the total
urinary proteins were separated by 1-D and 2-D electrophoresis
and then subsequently analyzed by Matrix Assisted Laser Desorption
Ionization-Time of Flight and Mass Spectrometer (MALDI-TOF/MS).
Furthermore, they were then fragmented with the aid of a Tandem
Mass Spectrometer (TOF/TOF) and the identified sequences aligned
and confirmed using similarity with the deduced primary structures
of members of the lipo-calin superfamily.
Results: The SDS-PAGE protein profiles showed
distinct proteins with molecular masses of 15, 22.4, 25, 28,
42, 50, 55, 68, and 91 kDa. Of these proteins, the 22.4 kDa
protein was considered to be target candidate. When 2D electrophoresis
was carried out, about ~50 spots were detected with different
masses and various pI ranges. The 22.4 kDa protein was found
to have a pI of about 4.9. This 22.4 kDa protein spot was
digested and subjected to mass spectrometry; it was identified
as rat MUP. The fragmented peptides from the rat MUP at 935,
1026, 1192, and 1303 m/z were further fragmented with the
aid of MS/MS and generated de novo sequence and this confirmed
this protein to be the MUP present in the urine of commensal
rats.
Conclusion: The present investigation confirms
the presence of MUP with a molecular mass of 22.4 kDa in the
urine of commensal rats. This protein may be involved in the
binding of volatile molecules and opens up a discussion about
how volatile and non-volatile molecules in the commensal rats’
urine may contribute chemo-communication.
[Back to top]
[Purchase
Article] [PMID:
20044924 PubMed - indexed for MEDLINE]
Drastic Effects on Fibril Formation of Amyloid-β
Peptides by the Addition of Amino Acid Residue Units to the
Termini
Y. Asanomi, Y. Kobayashi, H. Sakai, T. Masuda, X. Chen,
Y. Chuman, K. Uosaki and K. Sakaguchi
We report that the addition of amino acids to the amyloid
peptide dramatically affected the structure and the rate of
formation of amyloid fibrils. The attachment of three lysines
to Aβ(10-35)
gave the formation of remarkably long fibrils, while three
glutamates resulted in a faster formation rate of the fibrils.
[Back to top]
[Purchase
Article] [PMID:
19995336 PubMed - indexed for MEDLINE]
Prediction of Protein Subcellular Locations with
Feature Selection and Analysis
Y. Cai, J. He, X. Li, K. Feng, L. Lu, K. Feng, X. Kong
and W. Lu
In this paper, we propose a strategy to predict the subcellular
locations of proteins by combining various feature selection
methods. Firstly, proteins are coded by amino-acid composition
and physicochemical properties, then these features are arranged
by Minimum Redundancy Maximum Relevance method and further
filtered by feature selection procedure. Nearest Neighbor
Algorithm is used as a prediction model to predict the protein
subcellular locations, and gains a correct prediction rate
of 70.63%, evaluated by Jackknife cross-validation. Results
of feature selection also enable us to identify the most important
protein properties. The prediction software is available for
public access on the website http://chemdata.shu.edu.cn/sub22/,
which may play a important complementary role to a series
of web-server predictors summarized recently in a review by
Chou and Shen (Chou, K.C., Shen, H.B. Natural Science, 2009,
2, 63-92, http://www.scirp.org/journal/NS/).
[Back to top]
[Purchase
Article] [PMID:
19758117 PubMed - indexed for MEDLINE]
Band Assignment in Hemoglobin Porphyrin Ring Spectrum:
Using Four-Orbital Model of Gouterman
M.R. Dayer, A.A. Moosavi-Movahedi and M.S. Dayer
Band assignment for oxy, deoxy and methemoglobin using orbital
promotion is crucial to understanding inter-relation of electronic
transitions. Spectral changes may be correlated with conformational
alterations. Conformational changes of hemoglobin were interpreted
using fourorbital model of Gouterman. Our results indicated
that Goutherman model can predict the predominant conformations
of hemoglobin
[Back to top]
[Purchase
Article] [PMID:
19995344 PubMed - indexed for MEDLINE]
Herbivore Response in Passion Fruit (Passiflora
edulis Sims) Plants: Induction of Lipoxygenase Activity
in Leaf Tissue in Response to Generalist and Specialist Insect
Attack
B.C. Jardim, V.A. Perdízio, M.A. Berbert-Molina,
D.C. Rodrigues, S. Botelho-Júnior, A.C.P. Vicente,
E. Hansen, K. Otsuki, T.P. Ürményi and
T. Jacinto
Lipoxygenases (LOXs, EC 1.13.11.12) are a class of non-heme
iron containing dioxygenases which catalyze the regiospecific
and stereospecific hydroperoxidation of polyunsaturated fatty
acids with 1,4-pentadiene system such as linoleic acid and
linolenic acid in plants. In this work we studied the LOX
activity in damaged as well as in distal leaves in response
to specialist (Agraulis vanillae vanillae)
or generalist (Spodoptera frugiperda) insect attack.
Enzymatic assays showed that induction of LOX activity occurred
locally and systemically in response to both insects’
attacks. Northern blot analysis revealed that LOX expression
is also insect-inducible in agreement with enzymatic assay
results. In addition, northern analysis corroborated previous
reports that LOX activity is wound- and methyl jasmonate-inducible.
These results suggest that the herbivore-response in passion
fruit is mediated by jasmonates, since a key enzyme of the
biosynthetic pathway of jasmonic acid is induced upon lepidopteran
insects’ attacks.
[Back to top]
[Purchase Article] [PMID:
19995334 PubMed - indexed for MEDLINE]
Characterization of an mDock5-Specific Antibody and Tissue-Specific
Expression and Subcellular Localization of mDock5
E. Kim, J.-B. Yoon and S.K. Yoon
Rho GTPase controls multiple signal-transduction pathways
involving the actin cytoskeleton and the microtubule cytoskeleton
in processes such as the cell cycle, morphogenesis, and cell
migration. The activity of Rho GTPases, such as Rac1, Cdc42,
and RhoA, is regulated by GTPase-activating proteins (GAPs),
guanine nucleotide exchange factors (GEFs), and guanine nucleotide
dissociation inhibitor (GDI). The GEFs activate Rho GTPases
through exchange of GDP for GTP. A group of the GEF family,
CDM-GEF, containing the Dock180 Homology Region
2 (DHR2) domain is subdivided into four groups based on amino
acid sequences. One of these subgroups, DOCK-A, includes DOCK1,
DOCK2, and DOCK5, and activates Rac1 Rho GTPase. Mouse Dock5
(mDock5) is structurally similar to DOCK1 and composed of
1868 amino acids containing Src homology 3 (SH3), DHR1, DHR2,
and a proline-rich (PR) motif. We generated an mDock5-specific
antibody, which detected denatured and nascent forms of mDock5.
We determined tissue-specific expression patterns and subcellular
localization of mDock5 using this antibody. This antibody
provides a way to delineate the biological functions of mDock5
in vivo.
[Back to top]
[Purchase Article] [PMID:
19961430 PubMed - indexed for MEDLINE]
Human Hsp70/Hsp90 Organizing Protein (Hop) D456G Is a Mixture
of Monomeric and Dimeric Species
D.C. Gonçalves, L.M. Gava and C.H.I. Ramos
Hop is a tetratricopeptide repeat domain (TPR)-containing
co-chaperone that is able to directly associate with both
Hsp70 and Hsp90. Previous data showed that the TPR2A-domain
is the primary site for dimerization and that the TPR2B-domain
may also play a role in dimerization. We present Hop-D456G,
a mutant within the TPR2B-domain, that is a mixture of monomeric
and dimeric species.
[Back to top]
[Purchase
Article] [PMID:
19961431 PubMed - indexed for MEDLINE]
Click Chemistry Aided Synthesis of 1,4-Substituted
1,2,3-Triazole Based N-Fmoc Protected ε-Amino
Acids: Isolation, Characterization and Synthesis of Novel
Triazole Based Unnatural Amino Acids
V.V. Sureshbabu, N. Narendra, H.P. Hemantha and
G. Chennakrishnareddy
A new class of 1,4-substituted 1,2,3-triazole-based unnatural
amino acids is demonstrated by employing click reaction between
N-Fmoc amino alkyl azides and propiolic acid. The
resulting unnatural amino acids were isolated and then subjected
to Fmoc deprotection to isolate 1,2,3-triazole based amino
acids as stable solids. These new class of molecules were
also used for chain extension from both N- and C-terminals
to synthesize dipeptidomimetics bearing 1,2,3-triazole moiety
in the backbone.
[Back to top]
[Purchase
Article] [PMID:
20044922 PubMed - indexed for MEDLINE]
Identifying the Hierarchy of Dynamic
Domains in Proteins Using the Data of Molecular Dynamics Simulations
S.O. Yesylevskyy
The Hierarchical Domain-Wise Alignment (HDWA) technique of
domain identification in proteins is presented. HDWA is designed
to identify hierarchically organized dynamic domains in proteins
using the MD trajectories by eliminating systematic motions
from MD trajectories recursively in a model-free manner. The
method is tested on the proteins from different structural
classes.
[Back to top]
[Purchase
Article] [PMID:
19961432 PubMed - indexed for MEDLINE]
Bactericidal and Hemolytic Activities of Synthetic
Peptides Derived from Granulysin
A. Siano, G. Tonarelli, M.S. Imaz, J.C. Perín,
N. Ruggeri, M. López ,M.N. Santi and E. Zerbini
Granulysin is a human polypeptide produced by cytolytic cells
active against a broad range of microbes. Three peptides covering
the regions 25-50 (Gr-1 and Gr-2) and 39-62 (Gr-3) of granulysin
were synthesized, and their in vitro activity against
Mycobacterium tuberculosis was evaluated. The most
active peptide was Gr-1C, containing a disulphide bridge,
with Minimal Inhibitory Concentration value of 10.1 μM.
In concentrations of up to 50 μM,
Gr-1 and Gr2 didn’t exceed 30% of hemolysis.
[Back to top]
[Purchase
Article] [PMID:
19594427 PubMed - indexed for MEDLINE]
Antifungal Activity of Storage 2S Albumins from Seeds
of the Invasive Weed Dandelion Taraxacum officinale
Wigg.
T.I. Odintsova, E.A. Rogozhin, I.V. Sklyar , A.K. Musolyamov,
A.M. Kudryavtsev, V.A. Pukhalsky , A.N. Smirnov, E.V. Grishin
and T.A. Egorov
In this work, we isolated and characterized novel antifungal
proteins from seeds of dandelion (Taraxacum officinale
Wigg.). We showed that they are represented by five isoforms,
each consisting of two disulphide-bonded large and small subunits.
One of them, To-A1 was studied in detail, including N-terminal
amino acid sequencing of both subunits, and shown to display
sequence homology with the sunflower 2S albumin. Using different
assays we demonstrated that dandelion 2S albumins possess
inhibitory activity against phytopathogenic fungi and the
oomycete Phytophtora infestans at micromolar concentrations
with various isoforms differing in their antifungal activity.
Thus, 2S albumins of dandelion seeds represent a novel example
of storage proteins with defense functions.
[Back to top]
[Purchase
Article] [PMID:
19961428 PubMed - indexed for MEDLINE]
Fitting Evolution of Matrix Protein 1 from Influenza
A Virus Using Analytical Solution of System of Differential
Equations
S. Yan, Z. Li and G. Wu
The understanding of evolutionary mechanism is important,
and equally important is to describe the evolutionary process.
If so, we would know where the biological evolution will go.
At species level, we would know whether and when a species
will extinct or be prosperous. At protein level, we would
know when a protein family will mutate more. In our previous
study, we explored the possibility of using the differential
equation to describe the evolution of protein family from
influenza A virus based on the assumption that the mutation
process is the exchange of entropy between protein family
and its environment. In this study, we use the analytical
solution of system of differential equations to fit the evolution
of matrix protein 1 family from influenza A virus. Because
the evolutionary process goes along the time course, it can
be described by differential equation. The results show that
the evolution of a protein family can be fitted by the analytical
solution. With the obtained fitted parameters, we may predict
the evolution of matrix protein 1 family from influenza A
virus. Our model would be the first step towards the systematical
modeling of biological evolution and paves the way for further
modeling.
[Back to top]
[Purchase
Article] [PMID:
19594429 PubMed - indexed for MEDLINE]
Isolation and Characterization of a Novel Small Antifungal
Peptide from Bacillus megaterium D4 Ìsolated
from the Dung of Wild Plateau Yak in China
L. Chen and W. Chen
A novel small antifungal peptide-producing strain D4
was isolated from the dung of wild plateau yak and identified
as Bacillus megaterium. The purification procedure
of peptide consisted of acid precipitation, methanol extract
and C18 reverse-phase chromatography.
The amino acid composition of peptide YP differed from those
of antifungal peptides which have been reported to date. Peptide
YP was proved to be a novel small antifungal cyclic peptide.
It exhibited strong inhibitory activity against many phytopathogenic
fungi and had a wild range of thermo stability and pH stability
and was not susceptible to all proteases tested.
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