Biology subjects

Suwanto, A.

Publications and source records attributed to Suwanto, A..

3 recordsLinked to original sources

bioRxiv2024

Hydrolysis of palm kernel meal fibre using a newly isolated Bacillus subtilis F6 with high mannanase activity

High fibre content is the main limitation of using mannan-rich palm kernel meal (PKM) in feeding non-ruminant livestock. Microbial fermentation stands out as a cost-effective and environmentally friendly approach for hydrolysing fibre in lignocellulosic biomass. In this study, a Bacillus subtilis strain F6 with high mannanase secretion capability was isolated from an environmental source. Fermentation of PKM using strain F6 resulted in at least a 10% reduction in its neutral detergent fibre content. Notably, the strain exhibited a rapid response to PKM, with significant mannanase activity detected as early as 6 h, enabling fibre hydrolysis within a short fermentation period. Subsequent transcriptome analysis uncovered potential enzymes involved in PKM fibre degradation, and the purified recombinant enzymes were generated to assess their activity on PKM fibre degradation. {beta}-mannanase GmuG demonstrated strong hydrolysis activity of PKM fibre, and its biochemical properties were determined. Overall, the study reported the isolation of a B. subtilis strain suitable for fibre hydrolysis of mannan-rich biomass, followed by an investigation to identify and characterize the enzyme responsible for fibre degradation. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=146 SRC="FIGDIR/small/599806v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@50b8c8org.highwire.dtl.DTLVardef@1937688org.highwire.dtl.DTLVardef@4b0ab6org.highwire.dtl.DTLVardef@ac727a_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2022

Chromosome-level Reference Genome Provides Insights into Divergence and Stress Adaptation of the African Oil Palm

The palm family (Arecaceae), consisting of [~] 2600 species, is the third most economically important family of plants. The African oil palm (Elaeis guineensis) is one of the most important palms. However, the genome sequences of palms available are still limited and fragmented. Here, we report a high-quality chromosome-level reference genome of an oil palm Dura. The genome of 1.7 Gb was assembled by integrating long reads with [~] 150 x genome coverage. The assembled genome covered 94.5% of the estimated genome size, within which 91.6% were assigned into 16 pseudochromosomes and 73.7% were repetitive sequences. Relying on the conserved synteny with oil palm, the existing draft genome sequences of both date palm and coconut were further assembled into chromosomal level. Transposon burst, particularly long terminal repeat retrotransposons (LTRs) retrotransposons, following the last whole-genome duplication (WGD), likely explains genome size variation across palms. Convergent evolution of fruit colors tends to eliminate the roles of the virescens gene in controlling accumulation of anthocyanins in exocarp of ripe fruit of palms. Recent duplications of high tandemly repeated pathogenesis-related proteins (PRs) from the same tandem arrays played an important role in defense responses to Ganoderma. Whole genome re-sequencing of both ancestral African and introduced oil palms in Southeast Asia revealed that genes under putative selection were notably associated with stress responses, suggesting adaptation to stresses in the new habitat. The genomic resources and insights gained in this study could be exploited for accelerating genetic improvement and understanding the evolution of palms.

genomics↗

bioRxiv2020

Shotgun Metagenomic Analysis Reveals New Insights on Bacterial Community Profiles in Tempeh

ObjectiveAmplicon sequencing targeted 16S ribosomal RNA (rRNA) has been widely used for the analysis profile of the microbial community from fermented food samples. Previous results of 16S rRNA analysis metagenome showed that Firmicutes was the dominant phylum in tempeh. However, polymerase chain reaction (PCR) steps on amplicon sequencing analysis and intragenomic heterogeneity within 16S rRNA are believed to contribute to bias in the estimation of microbial community composition. An alternative approach known as shotgun metagenomic might be able to avoid this limitation. In this study, we employed total metagenomic DNA fragments sequenced directly for taxonomic dan functional profiling analysis. ResultTaxonomic profiling showed that Proteobacteria, Firmicutes, and Bacteroidetes were the dominant phyla from direct shotgun metagenomic analysis in all tempeh samples. In terms of composition, the shotgun metagenomic study revealed that Proteobacteria was the most relatively abundant phylum. Functional profiling showed that iron complex outer-membrane recepter protein (KEGG ID: K02014) was the most transcribed genes based on metagenome from tempeh samples.

microbiology↗