A novel class II Aldolase was isolated through metagenomic approach from Domas Crater, West Java, Indonesia. Sequence analysis of the enzyme was highly homolog to archaeal ribulose-5-phosphate 4-epimerase from uncultured Acidilobussp. with percent identityof 63%. Homological analysis of the protein shows that the protein sequence contains all conserved motifs of aldolase class II. The enzyme shows Zn 2+ binding, polypeptide binding, and active sites as other aldolase's. Phylogenetic analysis of the enzyme showed that the enzyme makes a different branch closed to ribulose-5-phosphate 4-epimerase of unculcured Acidilobus sp. The gene was expressed in E coli as a host, and produced 26kDa of protein. Further analysis of the enzyme showed that the enzyme is thermostable. In addition, the enzymewas purified through Ion Metal Affinity Chromatography and it showed as single band with the homogeneity at around 96%.

Whitening cream is a preparation or mixture of ingredients used on the outside of the body to brighten or change the color of the skin, resulting in clean and white skin. Many people, particularly women, use cosmetics to improve the appearance of their skin, one of which is whitening cream. Many producers saw this opportunity and added mercury and hydroquinone to increase the number of consumers because the product will be cheaper and provide faster results to their skin with these ingredients. This study aims to conduct a qualitative analysis of whitening creams circulating in Balikpapan. To achieve this goal, four samples A, B, C, and D were analyzed using the KI color test method, the flame test, and the color reagent method to determine the presence of mercury and hydroquinone.The findings of the qualitative test of the mercury and hydroquinone content in the whitening cream circulating in the city of Balikpapan revealed that three samples, namely samples B, C, and D, were known to contain mercury and two samples (samples A and D) were known to contain hydroquinone.

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Pada penelitian sebelumnya fragmen gen 1,9 kb telah berhasil diisolasi dari Kawah Domas, Jawa Barat melalui pendekatan metagenom. Fragmen tersebut diketahui mengandung daerah Open Reading Frame (ORF) utuh dari gen pengkode aldolase kelas II dari uncultured Acidilobus sp. yang kemudian disebut sebagai aldII. Fragmen gen aldII tersebut berhasil diekspresikan menjadi protein termostabil aldolase kelas II yang kemudian disebut sebagai AldII. Penelitian ini bertujuan untuk melakukan studi bioinformasi terhadap protein AldII tersebut. Protein AldII kemudian diketahui memiliki massa molekul ~21,2 kDa dengan rumus molekul C940H1539N261O281S8. Total residu bermuatan negatif (Asp + Glu) sebanyak 22 residu, sedangkan total residu bermuatan positif (Arg + Lys) adalah 18 residu. Nilai pI teoritis AldII sebesar 5,86. Hasil perhitungan indeks kestabilan protein ini adalah 36,61 dan diklasifikasikan sebagai protein yang stabil. Lewat penjajaran dengan homologi terdekat, ditemukan daerah lestari yang dapat menunjukan residu yang mungkin berperan dalam pengikatan logam dan sisi aktif. Prediksi struktur 3D dilakukan secara ab initio, menunjukan adanya 6 struktur β-sheet dan 6 struktur α-heliks. Dengan demikian dapat disimpulkan bahwa protein AldII dari uncultured Acidilobus sp. diduga memiliki aktivitas enzimatik.