The strong regulation of plant carbon allocation and growth by trehalose metabolism is important for our understanding of the mechanisms that determine growth and yield, with obvious applications in crop improvement. To gain further insight on the growth arrest by trehalose feeding, we first established that starch-deficient seedlings of the plastidic phosphoglucomutase1 mutant were similarly affected as the wild type on trehalose. Starch accumulation in the source cotyledons, therefore, did not cause starvation and consequent growth arrest in the growing zones. We then screened the FOX collection of Arabidopsis (Arabidopsis thaliana) expressing full-length cDNAs for seedling resistance to 100 mM trehalose. Three independent transgenic lines were identified with dominant segregation of the trehalose resistance trait that overexpress the bZIP11 (for basic region/ leucine zipper motif) transcription factor. The resistance of these lines to trehalose could not be explained simply through enhanced trehalase activity or through inhibition of bZIP11 translation. Instead, trehalose-6-phosphate (T6P) accumulation was much increased in bZIP11-overexpressing lines, suggesting that these lines may be insensitive to the effects of T6P. T6P is known to inhibit the central stress-integrating kinase SnRK1 (KIN10) activity. We confirmed that this holds true in extracts from seedlings grown on trehalose, then showed that two independent transgenic lines overexpressing KIN10 were insensitive to trehalose. Moreover, the expression of marker genes known to be jointly controlled by SnRK1 activity and bZIP11 was consistent with low SnRK1 or bZIP11 activity in seedlings on trehalose. These results reveal an astonishing case of primary metabolite control over growth by way of the SnRK1 signaling pathway involving T6P, SnRK1, and bZIP11.

Produksi bunga krisan (Chrysanthemum morifolium) terhambat oleh ketersediaan bibit, sehingga perlu diupayakan penelitian melalui kultur jaringan. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian BAP dan 2,4 D terhadap pembentukan kalus tanaman krisan. Penelitian menggunakan Rancangan Acak Lengkap (RAL). Perlakuan terdiri atas dua factor. BAP (0,0 mg/l, 1,0 mg/l, 1,5 mg/l dan 2,0 mg/l) dan 2,4 D (0,0 mg/l, 2,0 mg/l, 3,0 mg/l, 4,0 mg/l). Variabel yang diamati adalah waktu munculnya kalus, warna kalus dan tekstur kalus. Hasil penelitian menunjukkan bahwa ZPT BAP dan 2,4 D memiliki pengaruh terhadap waktu munculnya kalus. Kalus muncul paling cepat pada konsentrasi 2,0 mg/l 2,4 D dan kalus muncul paling lama pada konsentrasi 0,0 mg/l 2,4 D. Kalus tidak muncul pada perlakuan 0,0 mg/l BAP. Kombinasi BAP dan 2,4 D tidak memiliki pengaruh terhadap skor warna kalus dan tekstur kalus. Skor kalus tertinggi (7) diperoleh pada kombinasi perlakuan D0B1, D0B0,5 dan D0B2. Skor warna kalus terendah (1) diperoleh pada perlakuan D4B0.

Penelitian ini bertujuan untuk mengetahui sifat mekanik komposit serat pinang. Papan komposit serat pinang menggunakan resin polyester sebagai matrik pengikatnya. Serat pinang yang digunakan pada penelitian ini merupakan serat yang diperoleh dari buah pinang yang sudah tua dan tidak digunakan lagi. Sampel penelitian dibuat dengan memvariasikan konsentrasi serat yang digunakan (30%, 40%, 50% 60% dan 70%). Dari hasil pengujian yang dilakukan, terdapat perbedaan sifat mekanik material komposit serat pinang pada uji tarik dan uji tekan yang dilakukan. Pada uji tarik, komposit serat pinang dengan konsentrasi serat 50% merupakan serat dengan sifat mekanik paling baik karena memiliki, kuat tarik, pertambahan panjang dan beban maksimum yang paling tinggi, yaitu berturut-turut 16.

The objective of this research was to test antibacterial activity ethanol and ethyl acetate of lime peel (Citrus aurantifolia Swingle) extract by Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) against the growth of clinical isolate bacteria. The type of this study used laboratory experimental using sensitivity test, dilution of tube and spreading plate. The experimental design used Complete Random Design using three repetitions on three concentrations i.g 25, 50, and 75%. Data was analyzed by qualitative with measuring inhibit diameter zone bacterial and qualitative using Two Way Anova followed by BNT with α= 5%. The statistical analysis showed that the solvent factor and concentration factor was significantly against growing bacterial and there was an interaction affect of both factors on S. aureus growth. The result presented that the ethanol and ethyl acetate of lime peel extract strongly inhibited Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa; and midly inhibited the growth of Klebsiella pneumoniae. The MIC ethanol and ethyl acetate of lime peel extract against S. aureus, S. epidermidis and P. aeruginosa was 25% and K. pneumoniae was 50%. The MBC showed that ethanol and ethyl acetate of lime peel  extract killed bacteria P. aeruginosa at 15%, S. aureus, S. epidermidis at 20% and K. pneumoniae at 25%. Taken together, it can be concluded that ethyl acetate of lime extract more effective than that of ethanol extract was to inhibit and killed clinical isolate bacterial.Keywords: lime peel (Citrus aurantifolia Swingle), antibacterial activity, clinical isolate bacteria, MIC and MBC.

Small protein tyrosine phosphatase (PtpA) of Mycobacterium tuberculosis is attributed to the development of latent tuberculosis infection, and hence bocomes an interesting target for drug development. In this communication, inhibition of PtpA by naturally occurring fatty acids cis-2 and trans-2-eicosenoic acid is investigated. Mtb PtpA was heterologously expressed in Escherichia coli, and the activity of PtpA was inhibited by cis-2 and trans-2 eicosenoic fatty acids. Both compunds showed strong inhibition of PtpA activity with IC50 at low micromolar concentration. As comparison, trans-11-eicosenoic acid only slightly inhibit PtpA. In silico analysis confirmed the inhibition of PtpB by cis-2-eicosenoic acid by formation of several hydrogen bonds. These findings show that cis-2 and trans-2 eicosenoic fatty acids are potential candidates for latent tuberculosis inhibitors.

The present study aims at expressing and partially purifying PtpB in active form. To achieve this, Mtb PtpB gene has been cloned into pET30a vector and overexpressed in Escherichia coli BL 21(DE3) under IPTG induction in the form of an inclusion body. Following resolubilization by urea and dialysis, the resulted PtpB has been shown to be active against para-Nitrophenyl phosphate. It is concluded that the resulted PtpB has had been recovered from inclusion body to give the active form of the enzyme, and thus the success in overexpressing PtpB provides the required material to investigate the biochemical properties of the pathogen virulence factor further.

ABSTRAKTrehalose/T6P berperan penting bagi tahapan kehidupan tanaman dari tahap embryo, pertumbuahn vegetative, pertumbuhan generatif, hingga sanesensi melalui keterlibatannya dalam menentukan pembelahan sel, bentuk sel, arsitektur tanaman dan respon terhadap stress biotik dan abiotik. Mekanisme trehalose/T6P dalam peran tersebut melibatkan SnRK1 dan bZIP11 dengan mengintegrasikan antara ketersediaan dan penggunaan sumber karbon yang mempengaruhi pemrograman ekspresi gen-gen yang trerkait dalam anabolisme dan katabolisme serta gen-gen yang terlibat dalam respon tanaman terhadap stres biotik dan abiotik. Selain itu, protein-protein dalam lintasan metabolisme trehalose diduga terlibat juga dalam pemrograman dan aktivitas enzim-enzim target. Dengan mengetahui peran krusial metabolisme trehalose, manusia dapat memanfaatkan lintasan ini untuk kepentingan pertanian. The Roles of Trehalose Metabolism at Entire Plant Life ABSTRACTTrehalose/T6P has important role at entire plant stage of life starting from embryonic stage, vegetative growth, generative growth and senescence. The roles include cell devision, cell shape, plant architectecture, and plant responses to biotic and abiotic stress. Syncrunizing between energy demand and energy availability is the main mode of the roles through reprogramming of gene expression responsible for anabolism and/or catabolism processes depending on given situation including biotic and abiotic stress. Moreover, proteins of trehalose metabolism are suggested to affect enzyme activity of target proteins. SnRK1 and bZIP11 involve in all those modes. Understanding crusial roles of trehalose metabolism in plant therefore is necessary in order to get benefit from this pathway for agricultural issue.

The tropical climate in Indonesia supports the presence of many types of plants that have the potential to produce abundant vegetables and fruit, however the presence of fruit flies is an obstacle to fruit and vegetable productivity. Lemongrass and basil have been studied to contain several compounds that have the potential to control fruit fly attacks. This study aims to determine the effect of the ethanol extract of lemongrass pseudo stem (Cymbopogon citrates) and basil (Ocimum sanctum) leaves on the catch of Bactrocera fruit flies and to determine the concentration of the extract that has the highest number of catches. The method used in sampling was factorial randomized block design (RBD). The ethanol extract of the pseudo-lemongrass, the extract of basil leaves or the mixture of both extract (1:1) that was given at concentrations of 15%, 30% and 45% was dropped onto a piece of cotton and for then be put within a trap before placing on the tree. The cathes obtained from each extract at each concentration were observed if they show a significant difference in the number of fruit fly. Data were tested using analysis of variance (F test) at α = 0.05, followed by the Honest Significant Difference test (HSD). The results showed that the catch obtained from ethanol extract of lemongrass pseudo stem or from basil leaf ectract as well as  from their mixture had a significantly higher number of Bactrocera fruit flies than without using these extracts. The difference in extract concentration did not cause a difference in the ability to attract fruit flies. The conclusion of this study is that there is an effect of the  pseudo stem ethanol extract of lemongrass or basil leaf ectract as well as their mixture on the catch of Bactrocera fruit flies and these extract are recommended as non-synthetic pesticidesalternatives.