Completion of the amino acid sequence of papain

Papain was inhibited with bromo[2-(14)C]acetic acid, the tertiary structure of the inhibited enzyme was unfolded and the disulphide bridges were reduced with mercaptoethanol and aminoethylated. Digestion with trypsin gave a radioactive peptide consisting of residues 18-58 inclusive and containing therefore the sequence of the thirteen unknown residues 29-41 in the primary sequence of papain. This peptide was digested with pepsin to give a radioactive peptide consisting of residues 18-47, which after digestion with 0.4m-hydrochloric acid gave a radioactive peptide consisting of residues 24-43 inclusive. Further digestion with 6m-hydrochloric acid gave peptides that were used to determine the sequence: Ser-Ala-Val-Val-Thr-Ile-Glx-Gly-Ile-Ile-Lys-Ile-Arg for the residues 29-41, so completing the amino acid sequence of papain.     

Rapid in vitro propagation of Eclipta alba (L.) Hassk. through high frequency axillary shoot proliferation

An efficient protocol has been developed for rapid in vitro propagation of Eclipta alba L. (Asteraceae) through axillary bud multiplication. Murashige and Skoog (MS) medium supplemented with BA (10 M) was found to be most effective in breaking bud dormancy. An average number of 23 ± 0.57 shoots per explant was recorded after 30 days. Culture of node segments on fresh medium with lower concentration of BA (2 M) enhanced the multiplication rate. A maximum of 79 ± 1.90 mean number of shoots were obtained after three subcultures without any decline in multiplication rate. The regenerated microshoots showed the most efficient rooting on half strength MS medium augmented with 0.5 M IBA. Plantlets went through a hardening phase prior to ex vitro transfer and established in earthen pots containing garden soil; survival of about 90%. The established plants were uniform and exhibited morphological characters identical to mother plants.     

Sixth mycelial fraction acetone (6-MFA), an interferon inducer modulates acrylamide neurotoxicity

A single i.p. administration of an immunomodulatory agent 6-MFA (a biological response modifier and antiviral agent of fungal origin, 10 mg/100g b.wt.), on 5th day of repeated acrylamide (ACR, 50 mg/kg b.wt.) treatment significantly protected rats against its specific neurotoxic effects. Corpus striatal 3H-spiperone binding elevated (24%) while glutathione-S-transferase (GST) activity decreased (33%) in ACR group but values were markedly restored in 6-MFA alone and co-exposed group. Development of hind limb paralysis was also protected by 6-MFA. Results warrant the possible involvement of immune mechanisms and certain other factors such as lymphokines, hormones and microglia at the target site, which in turn facilitate the repair mechanism suggesting a therapeutic role of 6-MFA in clinical cases of toxic neuropathies in future.     

Inactivation and reactivation of horseradish peroxidase immobilized by various procedures.

Horseradish peroxidase (HRP) immobilized by coupling the amino acid side chain amino groups or carbohydrate spikes to the matrix has been studied for its resistance to heat, urea-induced inactivation and ability to regain activity after denaturation in order to understand the influence of the nature of immobilization procedure on these processes. The various immobilized preparations were obtained and their properties studied: Sp-HRP was obtained by direct coupling of HRP to cyanogen bromide-activated Sepharose, Sp-NHHRP by coupling periodate oxidized and diamine-treated enzyme to the cyanogen bromide activated Sepharose, SpNH-COHRP by coupling periodate-treated enzyme to amino-Sepharose and SpCon A-HRP by binding of the enzyme on Con A-Sepharose. All the immobilized preparations exhibited higher stability against heat-induced inactivation as compared to the native HRP. Sp-NHHRP was most stable followed by Sp-HRP, SpNH-COHRP and SpCon A-HRP. Sp-NHHRP was also superior in its ability to regain enzyme activity after thermal denaturation, although Sp-HRP regained maximum activity after urea denaturation. Inclusion of Ca2+ was essential for the reactivation of all preparations subsequent to denaturation by urea.     

The glycoflavone vicenin-2 its distribution in related genera within the labiatae

In a leaf flavonoid survey of Origanum the flavone C-glycoside, vicenin-2, was found to be restricted to the section Majorana. This is the first report of a glycoflavone in the Labiatae.     

Dopamine Modulates Option Generation for Behavior

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Stabilization of yeast invertase by insoluble immunocomplex formation using unfractionated glycosyl-specific and peptide specific polyclonal antiinvertase antibodies

Summary A strategy for the production of non-inhibitory polyclonal antisera for the immobilization of glycoenzymes is described. Insoluble complexes of invertase prepared using antiinvertase glycosyl antisera were more resistant to heat and urea induced denaturation than those prepared using antiinvertase antisera from which the glycosyl specific antibodies were removed. Unfractionated antiinvertase antibodies however gave most stable immunocomplexes with invertase.     

A Secure and Robust Compressed Domain Video Steganography for Intra- and Inter-Frames Using Embedding-Based Byte Differencing (EBBD) Scheme

This paper presents a novel secure and robust steganographic technique in the compressed video domain namely embedding-based byte differencing (EBBD). Unlike most of the current video steganographic techniques which take into account only the intra frames for data embedding, the proposed EBBD technique aims to hide information in both intra and inter frames. The information is embedded into a compressed video by simultaneously manipulating the quantized AC coefficients (AC-QTCs) of luminance components of the frames during MPEG-2 encoding process. Later, during the decoding process, the embedded information can be detected and extracted completely. Furthermore, the EBBD basically deals with two security concepts: data encryption and data concealing. Hence, during the embedding process, secret data is encrypted using the simplified data encryption standard (S-DES) algorithm to provide better security to the implemented system. The security of the method lies in selecting candidate AC-QTCs within each non-overlapping 8 × 8 sub-block using a pseudo random key. Basic performance of this steganographic technique verified through experiments on various existing MPEG-2 encoded videos over a wide range of embedded payload rates. Overall, the experimental results verify the excellent performance of the proposed EBBD with a better trade-off in terms of imperceptibility and payload, as compared with previous techniques while at the same time ensuring minimal bitrate increase and negligible degradation of PSNR values.