Annales Bogorienses

1-6

Authors: Dian Andriani, Ira Handayani, Wien Kusharyoto

Transferrin receptor (TfR) levels are elevated in various types of cancer cells and correlate with the aggressive or proliferative ability of tumor cells. Therefore, TfR levels are considered useful as a prognostic tumor marker, and TfR is a potential target for drug delivery in therapy of malignant cells. In such kind of targeted delivery system, antibody fragments are frequently used as targeting moiety. Here, we report the generation of an anti-TfR single-chain antibody variable (scFv). The cDNA encoding the variable of heavy and light chain domains of the scFv antibody fragment was derived from the anti-TfR monoclonal antibody of LUCA31. The gene encoding the anti-TfR scFv fragment was codon, optimized for expression in Escherichia coli, subsequently synthesized, and cloned into the pJExpress-804 Rhamex vector. The expression vector utilizes the E. colirhaB promoter and corresponds to the regulatory genes, and is tightly regulated by the presence of L-L-rhamnose. It is also tightly regulated in the absence of L-L-rhamnose by the addition of D-glucose The His6-tagged anti-TfR scFv fragment was expressed in E. coliNiCo21 and purified by means of immobilized metal chelate affinity chromatography on TALON™ matrix. In SDS-PAGE, a single band corresponding to a molecular mass of approximately 30 kDa was observed whether it corresponded to the predicted molecular mass based on the amino acid sequence.

9-18

Authors: Nina Artanti, Ian James Mcfarlane

Asparagine synthetase (AS) is one of the enzyme involves in ammonium metabolism in plant, it catalyzes the transfer of the amino group of glutamine to aspartate giving asparagine. Asparagine serves as a major nitrogen transport and storage molecule in many higher plants. This research used legume plant Coronilla rostrata callus culture for primary and secondary metabolism study. On primary metabolism, the culture were used to study the phenomenon of asparagine accumulation. Because of the responsiveness of the culture, we investigated the use of this culture for model system to conduct molecular biology study of the nitrogen metabolism. The aim of this study was to isolate...cDNAs enconding Asparagine synthetase from C. rostrata because of the asparagine accumulate in this culture. Several PCR based approaches were conducted such as RT-PCR, LM-PCR and RACE. Using these methods, two AS cDNAs was isolated from C. rostrata. AS1 (GenBank no AY081945) which a complete cDNA sequence and AS2 which a partial cDNA sequence. (GenBank no AF488726). These two cDNAs had high homology with the legume AS.

19-25

Authors: Amy Estiati, Yuli Sulistyowati, Fatimah Zahra, Ade Nena Nurhasanah, Syamsidah Rahmawati, Inez H S-Loedin

Transgenic rice plants harboring resistant gene to yellow stem borer, cry1B gene had been obtained. However, the cry1B gene in second generation of transgenic rice lines still segregating following Mendelian ratio 3:1. For further use in the breeding programs, it is important to ensure that the gene is dominant gene and the plants are homozygous for cry1B gene. Selection of homozygous transgenic rice lines containing cry1B gene at third, fourth and fifth generation had been conducted by PCR. The presence of cry1B gene was determined by showing the PCR product of 1.9 kb. Segregation analysis proved that six transgenic rice lines i.e. 3R7.8.15.1, 3R7.8.15.9, 3R7.8.15.10, 3R7.8.15.15, 3R7.8.15.21, 3R7.8.15.29 are homozygous lines for cry1B gene. Moreover, bioassay studies at vegetative stage on six homozygous transgenic rice lines showed that these transgenic rice lines are potential resistant to yellow stem borer comparing with non-transgenic plants, with the score of 0 (indicated no symptom) for six transgenic lines and score of9 (more than 60% damaged tillers ) for non-transgenic plants. However, to confirm the efficacy of cry 1B gene to yellow stem borer in natural condition, confined field trial in endemic area of yellow stem borer should be conducted.

23-28

Authors: Yuliasri Jamal, Aris Medta Pariwidjayanti, Andria Agusta

Steam distillation of essential oil from fresh leaves of Key Lime (Citrus aurantifolia Swingle) gave 0.4% yellow essential oil with distinctive fragrance. Five out of 40 components of the essential oil were identified as the major components with content above 5%, they were geranial (10.3%), limonene (10.2%), neral (8.94%), caryophyllene (5.72%), and citronellal (5.41%). The essential oil was active against four bacterial test, Bacillus subtilis NBRC 3134, Staphylococcus aureus NBRC 14276, Micrococcus luteus NBRC 14218, and Escherecia coli NBRC 14237. B. Subtilis was the most sensitive bacterium with the widest inhibition area at 50% concentration of essential oil. Minimum Inhibition Concentration (MIC) value of essential oil against B. Subtilis was 0.125%