Authors:L. Kredics, Kata Terecskei, Zsuzsanna Antal, A. Szekeres, L. Hatvani, L. Manczinger, and Cs. Vágvölgyi
isolates were screened for the production of proteolytic activities at 10 °C. Based on the activity profiles determined with paranitroanilide substrates at 5 °C, strain T221 identified as
was selected for further investigations. The culture broth of the strain grown at 10 °C in casein-containing culture medium was concentrated by lyophilization and subjected to gel filtration, which was followed by chromatofocusing of the fraction showing the highest activity on
-benzoyl-Phe-Val-Arg-paranitroanilide. The purified enzyme had a molecular weight of 24 kDa, an isoelectric point of 7.3 and a pH optimum of 6.2. The temperature optimum of 25 °C and the low thermal stability suggested that it is a true cold-adapted enzyme. Substrate specificity data indicate that the enzyme is a proteinase with a preference for Arg or Lys at the P1 position. The effect of proteinase inhibitors suggests that the enzyme has a binding pocket similar to the one present in trypsin.
Authors:Szilvia Kanizsai, Á. Ghidán, Eszter Újhelyi, D. Bánhegyi, and K. Nagy
Mutations in the HIV-1
gene associated with resistance to antiretroviral drugs in therapy-naïve Hungarian individuals transmitted as primary infection by their foreign sexual partners originated from African, Asian and other European countries had been analyzed. Drug resistance genotyping of HIV RT and PR genes were performed where mutations of 72 codons — among them 64 specific resistance codons representing 6
nucleoside reverse transcriptase inhibitor
non-nucleoside reverse transcriptase inhibitor
(NNRTIs) and 6
(PRIs) drugs — had been analyzed by Truegene HIV-1 Genotyping kit and OpenGene Sequencing System. Viral variants harboring resistance mutations in the
l gene were detected in 14% of the subjects. The highest rate of resistance to a single class of inhibitors was detected towards PR inhibitors (12%), followed by NRTI (8%) and NNRTI (5%). On the contrary, 25% of viruses transmitted by homosexual activity contained mutations led to resistance to NNRT. Viruses from 11 percent of cases were resistant to 2 classes of inhibitors, and 7 percent to three classes of inhibitors. Based upon sequence data non-B subtypes and CRFs were detected in more than 71% of cases. HIV-1 C (10.7%), HIV-F1 (7.2%) and HIV-1 G (3.6%) were detected as the more frequent subtypes. Among the HIV-1 recombinant viruses CRF02_AG variants were found more frequently (28.5%) followed by CRF06_cpx (17.8%) indicating penetration of non-B subtypes and recombinant African variants into Hungary, which raises serious clinical and public health consequences.
Authors:W. Cortez-Vega, G. Fonseca, B. Zanette, and C. Prentice
, S. , Visessanguan , W. & Thummaratwasiki , P. ( 2000 ): Inhibition of gel weakening of threadfin bream surimi using Thai legume seed proteinaseinhibitors . J. Food Biochem., 24 , 363 – 380