ORIGINAL_ARTICLE
Isolation and Characterization of a New Peroxisome Deficient CHO Mutant Cell Belonging to Complementation Group 12
We searched for novel Chinese hamster ovary (CHO) cell mutants defective in peroxisome biogenesis by an improved method using peroxisome targeting sequence (PTS) of Pex3p (amino acid residues 1–40)-fused enhanced green fluorescent protein (EGFP). From mutagenized TKaEG3(1–40) cells, the wild-type CHO-K1 stably expressing rat Pex2p and of rat Pex3p(1–40)-EGFP, numerous cell colonies resistant to the 9-(10-pyrene) nonanol/ultraviolet treatment were grown. These colonies were examined for intracellular location of Pex3p(1–40)-EGFP. By this method, we have isolated one CHO cell mutant, ZPEG403, which was found to belong to complementation group G (CG-G). Expression of the human peroxin, Pex3p cDNA encoding a 373-amino-acid peroxisomal membrane protein morphologically and biochemically restored peroxisome biogenesis, including peroxisomal membrane assembly, in ZPEG403 cells. Mutation and genomic DNA PCR analyses showed that, the dysfunction of Pex3p in ZPEG403, was due to one base (A) substitution in place of (G) in the first base of splicing site at the boundary of exon 6 and intron 6 of PEX3 gene, giving rise to remaining of all of intron 6, thereby inducing 81 bp insertion between positions 523–524 of PEX3 ORF, resulting in deletion of 200 amino acid residues from the C-terminus of Pex3p and a frame shift inducing both 18-amino-acid substitution and an early termination codon.
https://jsciences.ut.ac.ir/article_20099_ee484ea55aa5b84e0ee9f47bcf8858c3.pdf
2009-09-01
CHO cell mutant
Peroxin
Peroxisome biogenesis
PEX3
K.
Ghaedi
kamranghaedi@yahoo.com
1
AUTHOR
ORIGINAL_ARTICLE
Molecular Cloning and Characterization of a Lipase from an Indigenous Bacillus pumilus
Cloning and sequencing of a lipase gene from an indigenous Bacillus pumilus, strain F3, revealed an open-reading frame of 648 nucleotides predicted to encode a protein of 215 residues. Sequence analysis showed that F3 lipase contained a signal peptide composed of 34 amino acids with an H domain of 18 residues. A tat-like motif was found in the signal peptide similar to some other Bacillus pumilus lipases. High similarity was also observed between the protein sequences of the lipases from B. pumilus strains and F3 lipase especially near the catalytic triad, oxyanion hole and tentative lid. Expression of the lipase gene with its native signal peptide in Escherichia coli BL21 (DE3) led to accumulation of lipase as inclusion bodies in cytoplasm due to high hydrophobicity of the protein. Despite inclusion body formation, slight lipolytic activity was detected in periplasm as well as soluble cytoplasmic protein fractions which could show the presence of the recombinant lipase in the periplasmic space of host cell. This may indicate the processing of the lipase by its native signal peptide, although incapable to translocate the enzyme into the Escherichia coli periplasm completely.
https://jsciences.ut.ac.ir/article_20100_0843d865af187e75326e41ce068eaa2c.pdf
2009-09-01
Bacillus pumilus
Cloning
Escherichia coli BL21
Lipase
B.
Yakhchali
1
AUTHOR
ORIGINAL_ARTICLE
Molecular Identification of the Most Prevalent Mutations of Glucose-6-Phosphate Dehydrogenase (G6PD)
in Fars and Isfahan of Iran
Glucose-6-phosphate dehydrogenase (G6PD) in humans is in X-linked disorder, housekeeping enzyme and vital for the survival of every cell. It catalyses the oxidation of glucose-6-phosphate to 6-phospho Gluconat in the first committed step of the pentose phosphate pathway, which provides cells with pentoses and reducing power in the form of NADPH. NADPH is required to protect the cells against oxidative damage. The aim of this study was the molecular analysis of common G6PD mutations in the provinces of the Fars and Isfahan. The Study of G6PD deficiency was performed on 96 patients with a history of favism, consisted of 34 samples from Fars and 62 samples from Isfahan. Genomic DNA with specific oligonucleotide primers followed by digestion with restriction enzymes for known mutations such as; Mediterranean, Chatham, Cosenza, Aures, A-(202G-A/376A-G were carried out. The most common allele in Iran was found to be the G6PD Mediterranean (82.3%), followed by the G6PD Chatham (8.3%) and none of the samples had Cosenza or A-(G202A/A376G) mutation, and remained unknown (9.4%). Further sequencing required to search for the other mutations among the remained samples (9.4%).
https://jsciences.ut.ac.ir/article_20101_a072fd5465fde5dd8d7e308d45413212.pdf
2009-09-01
Chatham
G6PD deficiency
Mediterranean
M.R.
Noori-Daloii
1
AUTHOR
ORIGINAL_ARTICLE
Synthesis and Antimicrobial Activity of Some 2-[(4-Substituted-Phenyl-3-Chloro-Azetidin-2-One)-5-(2'-Methylamino-4-Phenyl-1', 3'-Thiazolyl-]-1, 3,4-Thiadiazoles
A new 2-[(4-substituted-phenyl-3-chloroazetidin-2-one)-5-(2'-methylamino 4-phenyl-1', 3'-thiazolyl-]-1, 3, 4-thiadiazoles, 5(a-n) were synthesized from 2-substituted-benzylideneamino-5-[2'-methylamino-4'-phenyl-1',3'-thiazolyl]-1,3, 4-thiadiazole, 4(a-n) using 2-amino-4phenyl-1, 3-thiazole as a starting material. The synthesised compounds have been screened in vitro for their antimicrobial activity against Bacillus subtilis, Escherichia coli. Klebsiella pneumoniae and Streptococcus aureus bacteria and Aspergillus niger, Aspergillus flavus, Fusarium oxisporium and Trichoderma viride fungi respectively. Some of the compounds displayed pronounced biological activity.
https://jsciences.ut.ac.ir/article_20102_09dacc6d973d294d22020aa5819f73f7.pdf
2009-09-01
2-Amino-4-phenyl-13-thiazole
Antimicrobial activity
Arylidene
Thiadiazole
S.D.
Srivastava
1
AUTHOR
ORIGINAL_ARTICLE
Planktonic Foraminifera Response to Sudden Global Warming in Late Maastrichtian, a Case Study from Ziyarat-Kola, Central Alborz, Iran
An abrupt global warming event has been recorded in many parts of the world in sediments of Latest Maastrichtian age between 65.45-65.10 Ma. This warm event was documented here at a section near Ziyarat-kola in Central Alborz based on analysis of planktonic foraminifera. An unusual abundance of normally large-size species such as Globotruncana arca, Globigerinelloides subcarinatus, Pseudoguembelina hariaensis and Rugoglobigerina rugosa in small-size fraction (63-150) was recorded. A similar trend of increasing in relative abundance of some opportunist species such as Guembelitria spp. was also recorded. At the same time, Laeviheterohelix dentata a long ranging dominant species, decreases considerably reflecting a high stress environmental condition as warming. Palynological studies show an increase in fungal spore and in thermophilic species confirming the result gained from foraminiferal analysis.
https://jsciences.ut.ac.ir/article_20103_408acec19f4893094ef3a2788e41f995.pdf
2009-09-01
Central Alborz
Global warming
Iran
Late Maastrichtian
Planktonic Foraminifera
M.
Asgharian Rostami
1
AUTHOR
ORIGINAL_ARTICLE
Magmatic Interaction as Recorded in Texture and Composition of Plagioclase Phenocrysts from the Sirjan Area, Urumieh-Dokhtar Magmatic Arc, Iran
Tertiary andesitic basalts of the Sirjan area, Urmieh-Dokhtar Magmatic Arc, Iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. Textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. The most common type of plagioclase phenocrysts have zoning patterns that display abrupt fluctuations in An content (more than 20 mol %) that correspond to well-developed dissolution surfaces. The less common type of plagioclase phenocrysts is characterised by a core with sieve texture, which is overgrown by oscillatory zoned rims. Changes in temperature, composition and H2O content of the surrounding melt caused the development of resorption zones in the engulfed plagioclases. In addition to the petrographical and mineral chemical evidences, Crystal Size Distribution (CSD) measurements show a kinked plot that reflects the effects of degassing and reveals mixing of two different phases of nucleation and growth. It is assumed that plagioclase phenocrysts originally crystallizing from the host magma were interrupted by mixing with a volatile-rich magma possessing low phenocryst content. The gradual loss of volatiles from plagioclase-saturated intrusive magma could be responsible for the sieve-textured core.
https://jsciences.ut.ac.ir/article_20104_443201ea8f2efcac8805e2ea9ace73c6.pdf
2009-09-01
CSD
Iran
Mixing
Sieve texture plagioclase
B.
Monfaredi
1
AUTHOR
ORIGINAL_ARTICLE
Evidence for Recent Large Magnitude Explosive Eruptions at Damavand Volcano, Iran with Implications for Volcanic Hazards
Damavand is a large dormant stratovolcano in the Alborz Mountains of northern Iran located in one of the most populous provinces, which could be adversely affected by tephra fall from Damavand. The youngest known eruption is a lava flow on the western flanks with an age of 7.3 ka. The volcanic products are predominantly porphyritic trachyandesite. Three major young pumice deposits, named here as Mallar, Karam Poshteh and Reyneh pumices, are identified, with provisional ages in the interval >7.3 ka and < 25 ka. The deposits cover much of the southern and western flanks of the volcano. The Mallar and Reyneh deposits consist of extensive basal pumice fall deposits with dispersal axes to the east, overlying pumiceous pyroclastic flow deposits extending up to 20 km from the summit and late-stage lahar deposits. The middle unit (Karam Poshteh) consists of a coarse-grained pumice fall deposit with proximal welded facies dispersed to the west, but lacks pyroclastic flow deposits. Based on reconnaissance field data they were formed by explosive eruptions of VEI4. Some of the villages on the flanks of the volcano are built on pyroclastic flow and lahar fans, and thus would be at high risk in the event of future explosive eruptions. We present an analysis of wind data and the applications of a computer tephra dispersal model to assess tephra fall hazards. Explosive eruptions of Damavand in the future would adversely affect large cities in the neighbouring provinces to the east, reflecting the dominant regional stratospheric wind directions.
https://jsciences.ut.ac.ir/article_20105_df61fa52c7657dc892baf50221738556.pdf
2009-09-01
Damavand Volcano
Explosive eruptions
Pyroclastic units
Volcanic hazards
M.
Mortazavi
1
AUTHOR
ORIGINAL_ARTICLE
Mineral Chemistry of Chlorite Replacing Biotite from Granitic Rocks of the Canadian Appalachians
Chlorite flakes, as a product of alteration of biotite, the dominant ferromagnesian mineral in the Paleozoic granitic rocks of the Canadian Appalachians, have been analyzed by electron microprobe for major elements and by 57Fe M?ssbauer spectroscopy for the coordination and oxidation state of Fe. Comparison of M?ssbauer Fe3+/Fe ratios obtained from chlorite and its host biotite indicates that chloritization might have occurred under relatively oxidizing conditions. Based on 54 analyzed samples, Si cation totals of these sheet silicates are less than 6.25 atoms per formula unit (apfu), and the sum of octahedral cations is very close to 12 both an indication of trioctahedral chlorite. The calculated mole fraction of chlorite in interlayered phase, Xc, ranges from. 0.72 to 0.98 confirming that the chlorites are completely free of any smectite layers. Compositional variations in chlorite are strongly controlled by host biotite and rock type. Fe/(Fe+Mg) ratio ranges from 0.35 to 0.93 and Si contents from 5.18 to 6.11 apfu lead to the classification of chlorites mainly as ripidolite and brunsvigite. All major elements in the chlorite are strongly correlated with each other. Fe/(Fe+Mg) ratio in biotite is well preserved by chlorite. Chlorite thermometry based on the variation in tetrahedral Al content within the chlorite structure shows a large variation in temperatures from 200 to 390 °C with an average of 340 °C. The chlorite from igneous rocks could also be used to detect reheating events and reveal the thermal history of the rocks.
https://jsciences.ut.ac.ir/article_20106_238db3d3c20923d5dd39100f7b4ce53e.pdf
2009-09-01
Alteration
biotite
Chlorite
Granite
A.A.
Tabbakh Shabani
1
AUTHOR
ORIGINAL_ARTICLE
Non-Abelian Sequenceable Groups Involving ?-Covers
A non-abelian finite group is called sequenceable if for some positive integer , is -generated ( ) and there exist integers such that every element of is a term of the -step generalized Fibonacci sequence , , , . A remarkable application of this definition may be find on the study of random covers in the cryptography. The 2-step generalized sequences for the dihedral groups studied for their periodicity in 2006 by H. Aydin and it is proved that in many cases for and , they are not periodic. Aydin’s work was in continuation of the research works of R. Dikici (1997) and E. Ozkan (2003) where they studied the ordinary Fibonacci sequences (sequences without the powers) of elements of groups. In this paper we consider 3-step generalized Fibonacci sequences and prove that the quaternion group Q (for every integer ) and the dihedral group (for every integer ) are sequenceable. The -covers together with the Fibonacci lengths of the corresponding 3-step sequences have been calculated as well.
https://jsciences.ut.ac.ir/article_20107_ddc9776940c70ef0a2cd62445ba297c8.pdf
2009-09-01
Fibonacci length
Finite groups
H.
Doostie
doostih@saba.tmu.ac.ir
1
AUTHOR