Iranian Journal of Biotechnology
Volume:2 Issue: 1, Winter 2004

There has been much interest generated in the recovery of nanoparticulate (nanoparticle) bioproducts (Second generation of biotechnological products) such as plasmid DNA and viruses as putative gene therapy vectors, macromolecular assemblies as drug delivery vehicles and virus-like particles as vaccine components. Such product must be manufactured in advanced stages of purity, material definition and sophisticated formulation to rival those demanded of the pharmaceutical macromolecules which dominate as the first generation products. Nanoparticulates are characterized by a critical size range (10-300 nm diameter) and complexity of surface chemistry and internal organisation which pose new challenges in separation science and engineering, controlled chemistries of modification and material measurement not readily addressed by extant technologies. Current review article is concerns with structural characterisations of nanoparticulate bioproducts as well as re-design of their downstream processing techniques which are common to all programmes. This focus is upon candidate partition systems which can contribute to the fractionation, recovery and purification of nanoparticulate assemblies from their soluble components (capsid proteins from virus, polynucleotides from plasmid DNA, soluble, agglomerated forms of protein etc.). The mechanistic design of new separation and formulation technologies based upon a sound understanding of quantifiable structural features of these nanoparticle bioproducts is strongly indicated.

In this study, twenty-five whey samples collected from dairy industries in the city of Isfahan. The samples were cultured on malt extract broth (MEB) and yeast extract glucose chloramphenicol agar (YGCA) media. Eleven yeast strains (designated M1 to M11) were isolated from the culture. The strains were identified by their morphological and physiological properties. Beta-galactosidase activity in the yeast strains showed that a strain of K. lactis designated as M2 had highest enzyme activity (up to 8103 EU/ml). The isolated yeast strains were examined for their ability in reduction of the biological oxygen demand (BOD). The results demonstrated a high level of reduction in the M2 strain. This strain was also found to have highest level of single cell protein (SCP), production (up to 11.79 g/l dry mass cell). The co-culture of the isolated yeast strains with Saccharomyces cerevisiae resulted in the highest biomass yield up to 22.38 g/l dry mass cell and significant reduction in initial BOD. Together, the data showed that the isolated yeast strain could be of valuable application in bioconversion of whey.

Methanolic leaf extracts of Eucalyptus camaldulensis were investigated for in vitro antifungal activities against Microsporum canis, Microsporum gypseum, Tricophyton rubrum, Tricophyton schoenleinii, Tricophyton mentagrophytes and Epedermophyton floccosum. The studies were carried out using broth dilution method, agar dilution method and inhibitory zone estimation. The effects of the plant extract were compared with those of griseofulvin. Eucalyptus camaldulensis showed antifungal activity against all the dermatophytes tested with MIC values ranging from 0.4 to 1.6 mg/mL using inhibitory zone estimation, 0.4-1.6 mg/mL using agar dilution method and 0.2 to 1.6 mg/mL using broth dilution method. The minimum fungicidal concentration (MFC) of the extracts ranged from 0.8 to 6.4 mg/mL. The results obtained suggest that E. Camaldulensis has anti-dermatophyte activity

Infection with Human T-cell Lymphotropic Virus Type I (HTLV-I) is a global health problem, affecting 10 to 20 million people around the world, including north-east of Iran. It has been recognized to be the etiologic agent of adult T-cell Leukemia and HTLV-I-associated Myelopathy. In both cases, the HTLV-I transactivator protein (Tax), plays crucial role. Monkeys are suitable host for a related virus called STLV, which together with HTLV are called Primate T-cell Lymphotropic Viruses (PTLVs). Primates are the only known hosts, in addition to human, to be able to develop malignant changes in the natural course of infection with PTLV-I and therefore, could be a valuable animal model for studies on this virus. In the present study, we report PCR-based detection and cloning of 1.8 kb pX region of a new PTLV in olive baboon (Papio anubis). Sequence alignments and phylogenic studies on nucleotide sequence of this region and amino acids of conceptually translated Tax protein showed that monkeys are infected with a PTLV much closer to HTLV-I sub-types a and b, rather than STLV-I. Moreover, analyses of its Tax protein suggest that it might have the same function as HTLV-I Tax proteins. Results of our study indicate the possibility of exploiting these baboons as an animal model of choice for evaluating a tax-based DNA vaccine to decrease the viral load of HTLV-I in carriers, in order to prevent the outcomes, as well as they may be utilized for other HTLV-I physiopathologic or therapeutic studies.

Cysteine proteinases (CPs) of Leishmania are considered to be attractive vaccine candidate in which their immunogenicity and immuno-modulatory effects have been confirmed. We have previously reported that a cocktail of two DNA plasmids encoding Leishmania major cysteine proteinases type I (CPB) and type II (CPA) induces a partial protective response in murine model of cutaneous leishmaniasis. The results also showed that the induced protective response was better than the responses given by each one the plasmids alone. However, in view of the capability of DNA plasmid for encoding several antigens, we investigated the possibility of using a single bivalent DNA vaccine, based on CP genes as an alternative mean of inducing protective immunity. Here we present evidence favoring that CPA and CPB delivered in the same plasmid DNA backbone either in separate locus or as a tandem fused gene induce partial protection against Leishmania major infection in susceptible BALB/c mice. Immunization of mice with these constructs promoted specific T-cell response of Th1 phenotype that is characterized by an increase in production of IFN-?. Our results confirm the previous observation about the possibility of DNA immunization against leishmaniasis using CP genes and lend support to the idea of using a single polyvalent plasmid DNA construct to elicit immune responses to several distinct antigens.

The frequencies of the Asian (M, BM) and European (N, J, K) mtDNA haplogroups in five major regions of Iran was investigated. Unexpectedly, the frequencies of the Asian haplogroups M and BM were low in Iran (2.34% for haplogroup M; 17.6% for haplogroup BM and 80.06% for haplogroup N). Almost identical frequencies for haplogroups J and K were found in the present study (10.81% and 10.14% for haplogroups J and K, respectively). On the other hand, the frequencies of haplogroups M and BM in Eastern regions were more than their frequencies in Western regions of the country. In contrast, the frequencies of haplogroups J and K in Western regions were more than their frequencies in Eastern regions of Iran. As a result, this study gives evidence for similarity between Iranian population ethnic groups and people from Northwest Asia and Southeast Europe. Our data suggest that Iranian tribes probably played a remarkable role in the formation of these ethnic groups. It gives the indication that the haplogroup J may be older than 6000-10000 years, and probably developed in Iran, and then expanded to different regions in Europe and Northwest Asia. On the other hand, it seems that the super-haplogroup M has developed after the inhabitants of Iran moved to Eastern Asia or this group migrated from Southern Iran/North of Arabian halve O to Pakistan and then to Asia.

Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system, with a complex etiology that includes a strong genetic component. The contribution of the major histocompatibility complex (MHC) has been established in numerous genetic linkage and association studies. In addition to the MHC, the chromosome 19q13 region surrounding the apolipoprotein E (APOE) gene has shown consistent evidence of involvement in MS. In a cross-sectional study, to show differences in APOE allele frequencies in multiple sclerosis compared with controls, we genotyped polymorphisms in four alleles namely;? 2,? 3 and? 4 alleles. This study was carried out on 81 patients with clinically definite MS and 93 asymptomatic, randomly selected elderly volunteers. A significant differences was observed in the distribution of? 4 allele between patients with MS and controls (9.3% vs. 0.5%;? 2=15.2; df=2; p<0.001). This provides strong support for the association of multiple sclerosis with APOE? 4 allele

In this study the mechanism of chromium (Cr) and copper (Cu) resistance in Pseudomonas aeruginosa was investigated. For this reason, 50 isolates of this micro-organism were separated from 345 burn patients hospitalized in burn unit of Kerman hospital, Iran, during May 2001 to April 2002. Susceptibility/resistance of the isolates to KCrO4, CuSO4, 5 H2O, AgNO3 and HgCl2 was determined by the agar dilution method. Among them, 6% were highly resistant to KCrO4 (MIC 50 mM), 56% were resistant to CuSO4, 5 H2O (MIC 10 mM), while, all the isolates were sensitive to HgCl2 and AgNO3 with MIC range 0.5 -1 mM, respectively. Metal resistant isolates exhibited different rate of Cr and Cu accumulation. Isolates 14, 39 and 50 accumulated 11,14 and 15 mM/g biomass chromate, similarly, isolate 24 accumulated 8 mM/g biomass copper. The accumulation of Cr and Cu was mainly surface bound (biosorption), since considerable quantity of these heavy metals was lost from the cell biomass after treating the cells with 50 mM EDTA. Furthermore, P. aeruginosa isolates did not produce H2S. X-ray diffraction analysis of the cell surface exposed to the above heavy metal ions revealed that Cr and Cu were mainly deposited on the cell surface in the form of chromium and copper sulfide (CrS and CuS). These complexes were in the form of electron dense nanoparticles ranging in size from 10 to 40 nm in diameter. However, cells treated with EDTA did not show such complexes.