ocky radjasa
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ANTIBACTERIAL ACTIVITY OF A SECONDARY METABOLITE-PRODUCING CORAL BACTERIUM Pseudoalteromonas SPECIES ocky radjasa; Torben Marten; Thorsten Brinkoff; Hans-Peter Grossart; Agus Sabdono; Meinhard Simon
JOURNAL OF COASTAL DEVELOPMENT Vol 7, No 2 (2004): Volume 7, Number 2, Year 2004
Publisher : JOURNAL OF COASTAL DEVELOPMENT

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Abstract

A bacterium, collected at the surface of coral Acropora sp., TAB4.2 was successfully screened for secondary metabolites production based on PCR amplification of the non-ribosomal peptide synthetase gene. It was identified as closely related to Pseudoalteromonas luteoviolacea based on its 16S rDNA. TAB4.2 was found to inhibit the growth of all 5 coral-associated and all 5 pathogenic bacteria tested. To characterize the inhibiting metabolite, a 279 bp long DNA fragment was obtained and the deduced amino acid sequence showed conserved signature regions for peptide synthetases and revealed a high similarity to NosD (40 % identity), a multifunctional peptide synthetase from Nostoc sp. GSV224, and NdaB (44 % identity), a peptide synthetase module of Nodularia spumigena. �m es�`� ��� on their ecology. Due to this, water quality management in these ecosystems has become a necessity. Regular studies of the hydrological parameters are essential for this purpose, as they can assess the status of pollution and help in deciding the mitigation strategy.  Water quality of 26 km stretch of Thane creek, central-west coast of India was analyzed in 5 regions of the creek from May 1999 to April 2000. The study revealed spatial and temporal patterns. Heavy suspended solid load (avg. 5.736 gm/L), frequent hypoxia (DO<2.5 mg/L) coupled with excess nutrients like Phosphate-Phosphorus (avg. 0.26 mg/L) and Nitrate-Nitrogen (avg. 0.96 mg/L) were the main features of the creek. The Thane city region showed more deterioration of water quality compared to the other regions in the creek. In this region the suspended solid load showed an increase of 713.69% and dissolved oxygen decreased by 21.55% compared to the data of 1992-93. This can be attributed to the severe onslaught of activities in this region like solid waste dumping, construction of 3 new bridges, etc. since 1993, thereby affecting the flushing characteristic. Hence in order to protect and preserve such ecosystems, alterations to the environment should be meticulously planned.  
MARINE INVERTEBRATE-ASSOCIATED BACTERIA IN CORAL REEF ECOSYSTEMS AS A NEW SOURCE OF BIOACTIVE COMPOUNDS ocky radjasa
JOURNAL OF COASTAL DEVELOPMENT Vol 7, No 2 (2004): Volume 7, Number 2, Year 2004
Publisher : JOURNAL OF COASTAL DEVELOPMENT

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Abstract

Coral reefs are the most species-rich environments in the oceans. Reefs cover 0.2% of the ocean’s area and yet they provide home to one-third of marine fishes and to tens of thousands of other species. Coral reefs provide essential fish habitat, support endangered and threatened species, and harbor protected marine mammals. Despite the obvious ecological value of these habitats, most coral reefs around the world, including Indonesia’s, are threatened or already being destroyed by human activities. The search for bio-active compounds extracted from coral reef invertebrates which is emerging as an area of increasing interest among biotechnological companies, further threatens the integrity of the reef ecosystem. It would be of great interest to find alternative sources of these compounds, in order to preserve this precious environment and also to obtain higher amounts of these bi-active molecules. Increasing observations suggest that a number of bio-active metabolites obtained from invertebrates are in fact produced by associated microorganisms: this has prompted research into the rapidly expanding field of study of metabolites derived from microorganisms associated with reef invertebrates. The possibility to culture relevant microorganisms in bioreactors would enable the production of large amounts of the bio-molecules of interest, at the same time preserving the marine ecosystem from exploitation.
CORALS AS SOURCE OF BACTERIA WITH ANTIMICROBIAL ACTIVITY ocky radjasa; Jutta Wiese; Agus Sabdono; Johannes F Imhoff
JOURNAL OF COASTAL DEVELOPMENT Vol 11, No 3 (2008): Volume 11, Number 1, Year 2008
Publisher : JOURNAL OF COASTAL DEVELOPMENT

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Abstract

In this study we examined marine bacteria associated with different corals (Porites lutea, Galaxea fascicularis, Acropora sp. and Pavona sp.) collected from vicinity of Panjang island, Jepara, North Java Sea, Indonesia for their antimicrobial activities against the bacteria Echerichia coli, Bacillus subtilis, Staphylococcus lentus and the yeast Candida glabrata. A total of 13 bacterial isolates belonged to the members of Bacillus, Vibrio, Micrococcus, Pseudoalteromonas, Arthrobacter and Pseudovibrio were found to inhibit the growth of at least one test strain. Further examinations among the biologically active strains by using PCR with specific primers of non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) resulted in the presence of NRPS gene fragments in the 2 members of Bacillus and Micrococcus and PKS gene fragments in the 2 members of Bacillus and Vibrio. Following cloning and sequencing of the PCR products, the fragments from Bacillus BM1.5 and Micrococcus BJB showed sequence identity with peptide synthetase genes of Bacillus subtilis (61 %) and Actinoplanes teichomyceticus (62.4%). On the other hand, PKS-amplifying strains Bacillus BJ.7 and Vibrio MJ.5 showed closest sequence identity with polyketide synthase genes of Bacillus subtilis (73%) and Anabaena sp 90 (62%), respectively.