Asymmetric synthesis of (S)-ethyl-4-chloro-3-hydroxybutanoate using Candida parapsilosis ATCC 7330

Asymmetric reduction of ethyl-4-chloro-3-oxobutanoate to (S)-ethyl-4-chloro-3-hydroxybutanoate in aqueous medium by resting cells of Candida parapsilosis ATCC 7330 was optimized. The influence of culture parameters (inoculum size, inoculum age and biocatalyst harvest time) and reaction parameters (co-substrate, resting cell, pH and substrate concentrations) on the asymmetric reduction were studied. It was found that these parameters significantly influenced the rate of the asymmetric reduction. Under the optimum conditions, the final concentration of (S)-ethyl-4-chloro-3-hydroxybutanoate, enantiomeric excess and the isolated yield of (S)-ethyl-4-chloro-3-hydroxybutanoate were 1.38 M (230 g/l), >99 and 95%, respectively. The space time yield was 115 mmol/lh, which is significantly higher than other whole cell biocatalysts reported so far.     

White Spot Syndrome Virus infection in Penaeus monodon is facilitated by housekeeping molecules

White Spot Syndrome Virus (WSSV) is a major pathogen in shrimp aquaculture, and its rampant spread has resulted in great economic loss. Identification of host cellular proteins interacting with WSSV will help in unravelling the repertoire of host proteins involved in WSSV infection. In this study, we have employed one-dimensional and two-dimension virus overlay protein binding assay (VOPBA) followed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify the host proteins of Penaeus monodon that could interact with WSSV. The VOPBA results suggest that WSSV interacted with housekeeping proteins such as heat shock protein 70, ATP synthase subunit β, phosphopyruvate hydratase, allergen Pen m 2, glyceraldehyde-3-phosphate dehydrogenase, sarcoplasmic calcium-binding protein, actin and 14-3-3-like protein. Our findings suggest that WSSV exploits an array of housekeeping proteins for its transmission and propagation in P. monodon.     

Certain observations on Scytonema stuposum (Kuetz.) Born. (Cyanophyta,Nostocales)

Some interesting cultural observations on Scytonema stuposum (Kuetz.) Born., were recorded. It was observed that frequently one or more terminal cells of a branch get cut off but they still remain attached over the sheath of the mother filament. Even in this condition such structures continue their growth and may become a multicellular body. Later, such a structure gets detached from the mother filament and serve as a hormogonium.     

Metabolism of cholesterol by callus culture of Holarrhena antidysenterica

A chemically defined medium was established for the growth of tissue cultures of Holarrhena antidysenterica. Administration of cholesterol-[4-¹⁴C] to 10-day-old callus yielded radioactive 24-methylenecholesterol, 28-isofucosterol, sitosterol, stigmasterol, and conessine, thereby indicating that the conversion of cholesterol into sitosterol is mediated through 24-methylenecholesterol and 28-isofucosterol in this system.     

Cytodiagnosis of granulocytic sarcoma of liver arising in a milieu of myeloid metaplasia: a case report

BACKGROUND: Granulocytic sarcoma is an extramedullary tumor that is composed of granulocytic precursor cells. We report an unusual case of granulocytic sarcoma of the liver that arose in the background of myeloid metaplasia. Fine needle aspiration cytology (FNAC) was instrumental in making the diagnosis in absence of previously known Hematlogic abnormality. CASE: A 65-year-old woman presented with multiple nodules in the liver. USG-guided FNAC was performed on them. The aspirates showed many myeloid blasts, myelocytes, metamyelocytes, erytbroid precursors and lympboglandular bodies. We considered a differential diagnosis of granulocytic sarcoma and myeloid metaplasia. The presence of erytbroid precursors prompted us to consider myeloid metaplasia as a differential diagnorsis of granulocytic sarcoma. Peripberal smear showed a leukoerytbroblastic reaction. The patient died, and necropsy from the liver revealed extensive infiltration by undfferentiated blast cells with areas of myeloid metaplasia showing maturing erytbroid, myeloid and megakaryocytic elements. CONCLUSION: When a dual population of predominant myeloid blasts and normoblarts is encountered, a suspicion of granulocytic sarcoma arising in a background of myeloid metaplasia must be kept. Cells of all 3 lineages may not be always seen in myeloid metaplasia, and 1 cell line may predominate, causing a diagnostic dilemma.     

Administration of E2 and NS1 siRNAs Inhibit Chikungunya Virus Replication In Vitro and Protects Mice Infected with the Virus

Background

Chikungunya virus (CHIKV) has reemerged as a life threatening pathogen and caused large epidemics in several countries. So far, no licensed vaccine or effective antivirals are available and the treatment remains symptomatic. In this context, development of effective and safe prophylactics and therapeutics assumes priority.

Methods

We evaluated the efficacy of the siRNAs against ns1 and E2 genes of CHIKV both in vitro and in vivo. Four siRNAs each, targeting the E2 (Chik-1 to Chik-4) and ns1 (Chik-5 to Chik-8) genes were designed and evaluated for efficiency in inhibiting CHIKV growth in vitro and in vivo. Chik-1 and Chik-5 siRNAs were effective in controlling CHIKV replication in vitro as assessed by real time PCR, IFA and plaque assay.

Conclusions

CHIKV replication was completely inhibited in the virus-infected mice when administered 72 hours post infection. The combination of Chik-1 and Chik-5 siRNAs exhibited additive effect leading to early and complete inhibition of virus replication. These findings suggest that RNAi capable of inhibiting CHIKV growth might constitute a new therapeutic strategy for controlling CHIKV infection and transmission.     

Genetic Characterization of the Influenza A Pandemic (H1N1) 2009 Virus Isolates from India

Background

The Influenza A pandemic H1N1 2009 (H1N1pdm) virus appeared in India in May 2009 and thereafter outbreaks with considerable morbidity and mortality have been reported from many parts of the country. Continuous monitoring of the genetic makeup of the virus is essential to understand its evolution within the country in relation to global diversification and to track the mutations that may affect the behavior of the virus.

Methods

H1N1pdm viruses were isolated from both recovered and fatal cases representing major cities and sequenced. Phylogenetic analyses of six concatenated whole genomes and the hemagglutinin (HA) gene of seven more isolates from May-September 2009 was performed with reference to 685 whole genomes of global isolates available as of November 24, 2009. Molecular characterization of all the 8 segments was carried out for known pathogenic markers.

Results

The first isolate of May 2009 belonged to clade 5. Although clade 7 was the dominant H1N1pdm lineage in India, both clades 6 and 7 were found to be co-circulating. The neuraminidase of all the Indian isolates possessed H275, the marker for sensitivity to the neuraminidase inhibitor Oseltamivir. Some of the mutations in HA are at or in the vicinity of antigenic sites and may therefore be of possible antigenic significance. Among these a D222G mutation in the HA receptor binding domain was found in two of the eight Indian isolates obtained from fatal cases.

Conclusions

The majority of the 13 Indian isolates grouped in the globally most widely circulating H1N1pdm clade 7. Further, correlations of the mutations specific to clade 7 Indian isolates to viral fitness and adaptability in the country remains to be understood. The D222G mutation in HA from isolates of fatal cases needs to be studied for pathogenicity.