Sequencing and Comparative Genomic Analysis of a Highly Metal-Tolerant Penicillium janthinellum P1 Provide Insights Into Its Metal Tolerance

Heavy metal pollution is a global knotty problem and fungi hold promising potential for the remediation of wastewater containing heavy metals. Here, a new highly chromium-tolerance species, Penicillium janthinellum P1, is investigated. The genome of P1 was sequenced and assembled into 30 Mb genome size containing 10,955 predicted protein-coding genes with a GC content of 46.16% through an integrated method of Illumina short-read sequencing and single-molecule real-time Pacific Biosciences sequencing platforms. Through a phylogenetic analysis with model species of fungi, the evolutionary divergence time of Penicillium janthinellum P1 and Penicillium oxalicum 114-2 was estimated to be 74 MYA. 33 secondary metabolism gene clusters were identified via antiSMASH software, mainly including non-ribosomal peptide synthase genes and T1 polyketide synthase genes. 525 genes were annotated to encode enzymes that act on carbohydrates, involving 101 glucose-degrading enzymes and 24 polysaccharide synthase. By whole-genome sequence analysis, large numbers of metal resistance genes were found in strain P1. Especially ABC transporter and Superoxide dismutase ensure that the P1 fungus can survive in a chromium-polluted environment. ChrA and ChrR were also identified as key genes for chromium resistance. Analysis of their genetic loci revealed that the specific coding-gene arrangement may account for the fungus’s chromium resistance. Genetic information and comparative analysis of Penicillium janthinellum are valuable for further understanding the mechanism of high resistance to heavy metal chromium, and gene loci analysis provides a new perspective for identifying chromium-resistant strains.

Draft Genome Sequence of Bacillus cereus TN10, a Chromium-Resistant and -Reducing Strain Isolated from Tannery Effluent

ABSTRACT Here, we present the draft genome sequence of Bacillus cereus strain TN10, which exhibited chromium resistance and chromium-reducing ability. The whole-genome sequence analysis of strain TN10 will help us to understand its genetic factors involved in the bioremediation of Cr6+.

Analyzing the Mechanism and Effect of Acid Protease in Wet blue Bating Process for Leather Production

In recent years, in order to reduce the pollution produced in beam-house and tanning sections, more and more tanneries purchase wet blue from other factories in other regions directly used as raw materials for finished leather production thereby those polluted preliminary steps can be eliminated. Therefore, the wet blue bating process is an essential step to minimize the differences of wet blue which are purchased from different regions. In this study, the properties of different acid protease are analyzed for selecting suitable protease used for wet blue bating. The analysis of chromium tolerance of different acid proteases reveals that, L1 and L4 produced from Aspergillus have higher chromium resistance than that of produced from Bacillus. The effect of L1 and L4 on wet blue and collagen shows that the L1 has more excellent performance, in which the molecular weight of functional protein is 48 KD. By SEM and MCT analysis, L1 can successfully disperse the collagen fibers of wet blue. Furthermore, the biodegradation rates of collagen and elastin were 0.006‰ and 0.5‰, respectively. It indicates that the acid protease mainly degraded elastin but not collagen in bating process thereby ensuring production safety. This paper provides the importance references for the application and the basis for the development of mechanism of acid protease in bating process.