Phycicoccus flavus sp. nov., a novel endophytic actinobacterium isolated from branch of Kandelia candel.

A Gram-stain-positive, aerobic, non-motile, non-endospore-forming and rod-shaped actinobacterium, designated strain CMS6Z-2T, was isolated from a surface-sterilized branch of Kandelia candel collected from the Maowei Sea, Guangxi Zhuang Autonomous Region, PR China. Strain CMS6Z-2T grew at 10-37 °C (optimum, 37 °C), pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-10.0 % (w/v) NaCl (optimum, 0-1.0 %). Strain CMS6Z-2T possessed meso-diaminopimelic acid as the diamino acid of the peptidoglycan and MK-8 (H4) as the predominant menaquinone. The major fatty acids were iso-C15 : 0, C16 : 0 and C18 : 1 ω9c. The polar lipids comprised diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and two unknown phospholipids. The G+C content of the genomic DNA was 74.1 mol%. Comparative analysis of 16S rRNA genes showed that strain CMS6Z-2T should be assigned to the genus Phycicoccus and its closest relative was Phycicoccus endophyticus IP6SC6T with 98.3 % similarity. Phylogenetic analyses based on 16S rRNA gene sequence and phylogenomic analysis based on core proteomes alignment revealed that strain CMS6Z-2T belonged to the genus Phycicoccus and formed a robust cluster with Phycicoccus endophyticus IP6SC6T within the genus Phycicoccus. The average nucleotide identity value and estimated digital DNA-DNA hybridization value between strain CMS6Z-2T and the type strain of Phycicoccus endophyticus were 81.5 and 23.9 %, respectively. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain CMS6Z-2T represents a novel species of the genus Phycicoccus, for which the name Phycicoccus flavus sp. nov. is proposed. The type strain is CMS6Z-2T (=KCTC 49240T=CGMCC4.7549T).

Phycicoccus avicenniae sp. nov., a novel endophytic actinomycete isolated from a branch of Avicennia mariana.

A novel endophytic actinomycete, designated strain BSK3Z-2 T, was isolated from a surface-sterilised branch of Avicennia mariana from Shankou Mangrove Nature Reserve, Guangxi Zhuang Autonomous Region, China. Cells were observed to be Gram-stain positive, aerobic, asporogenous and rod-shaped. Strain BSK3Z-2 T was found to grow optimally at 30 °C, pH 7.0 and in the presence of 1% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain BSK3Z-2 T belongs to the genus Phycicoccus and has high 16S rRNA gene sequence similarity of 98.1% with Phycicoccus endophyticus IP6SC6T. Phylogenetic analysis based on the genome of strain BSK3Z-2 T was performed by extracting and aligning 39 conserved proteins and 88 housekeeping genes, which further confirmed the phylogenetic assignment of strain BSK3Z-2 T. The draft genome of strain BSK3Z-2 T is 3.54 Mbp with a DNA G + C content of 73.8%. The average nucleotide identity (ANI), amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strain BSK3Z-2 T and species of genus Phycicoccus were 73.8-85.6%, 64.5-75.9% and 19.5-23.8%, respectively, which are below the standard cut-off values for bacterial species delineation. Strain BSK3Z-2 T contains MK-8(H4) as the dominant menaquinone. The cell wall peptidoglycan contains meso-diaminopimelic acid. The polar lipids profile of strain BSK3Z-2 T was found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. The predominant fatty acids were identified as C15:0, C17:0, iso-C16:0 and C17:1ω8c. Comparing the phenotypic and phylogenetic features of the strain BSK3Z-2 T and related taxa, strain BSK3Z-2 T is concluded to represent a novel species of the genus Phycicoccus, for which the name Phycicoccus avicenniae sp. nov. is proposed. The type strain is BSK3Z-2 T (= CGMCC 1.18743 T = JCM 34335 T).

Demystifying polyphosphate-accumulating organisms relevant to wastewater treatment: A review of their phylogeny, metabolism, and detection.

Currently, the most cost-effective and efficient method for phosphorus (P) removal from wastewater is enhanced biological P removal (EPBR) via polyphosphate-accumulating organisms (PAOs). This study integrates a literature review with genomic analysis to uncover the phylogenetic and metabolic diversity of the relevant PAOs for wastewater treatment. The findings highlight significant differences in the metabolic capabilities of PAOs relevant to wastewater treatment. Notably, Candidatus Dechloromonas and Candidatus Accumulibacter can synthesize polyhydroxyalkanoates, possess specific enzymes for ATP production from polyphosphate, and have electrochemical transporters for acetate and C4-dicarboxylates. In contrast, Tetrasphaera, Candidatus Phosphoribacter, Knoellia, and Phycicoccus possess PolyP-glucokinase and electrochemical transporters for sugars/amino acids. Additionally, this review explores various detection methods for polyphosphate and PAOs in activated sludge wastewater treatment plants. Notably, FISH-Raman spectroscopy emerges as one of the most advanced detection techniques. Overall, this review provides critical insights into PAO research, underscoring the need for enhanced strategies in biological phosphorus removal.

Phycicoccus mangrovi sp. nov., a novel endophytic actinobacterium isolated from bark of Sonneratia apetala.

Two novel strains KQZ13P-1T and MAQZ13P-2 were isolated from bark of Sonneratia apetala collected from Maowei sea Mangrove Nature Reserve in Guangxi Zhuang Autonomous Region, China. Two strains were Gram-positive, aerobic, non-spore-forming, no diffusion pigment actinobacterial strains and investigated by a polyphasic approach to determine their taxonomic position. The average nucleotide identity (ANI) value and the digital DNA-DNA hybridization (dDDH) value between the two strains were 99.9% and 99.7%, respectively, suggesting that they belonged to the same species. The ANI and dDDH values between strain KQZ13P-1T and five Phycicoccus species were 74.4-95.3% and 20.1-61.5%, respectively. Phylogenetic analyses based on 16S rRNA gene sequences showed that the two strains were member of the genus Phycicoccus and were closely related to P. jejuensis NRRL B-24460T (99.2% sequence similarity), followed by P. ginsengisoli DCY87T (97.5-97.6%). Moreover, based on 88 core genes, the phylogenomic tree indicated that the two strains clustered with P. jejuensis NRRL B-24460T. The cell-wall peptidoglycan of both strains contained meso-diaminopimelic acid. The major fatty acids in two strains were C17:1ω8c, iso-C15:0 and iso-C16:0. The major polar lipids included diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) and phosphatidylinositol (PI). Based on phylogenetic, phenotypic and chemotaxonomic analysis, strains KQZ13P-1T and MAQZ13P-2 represent a novel species of the genus Phycicoccus, for which the name Phycicoccus mangrovi sp. nov. is proposed. The type strain is KQZ13P-1T (=CGMCC 1.18973T = JCM 34556T).

Bacterial isolates degrading ritalinic acid-human metabolite of neuro enhancer methylphenidate.

The consumption of nootropic drugs has increased tremendously in the last decade, though the studies on their environmental fate are still scarce. Nootropics are bioactive compounds designed to alter human's physiology therefore the adverse effects towards wildlife can be expected. In order to understand their environmental impact, the knowledge on their transformation pathways is necessary. Methylphenidate belongs to the most prescribed neuro-enhancers and is among the most favored smart drugs used in non-medical situations. It is metabolized in human liver and excreted as ritalinic acid. Here, we showed for the first time that ritalinic acid can be biodegraded and used as a sole carbon and nitrogen source by various microbial strains originating from different environmental samples. Five axenic strains were isolated and identified as: Arthrobacter sp. strain MW1, MW2 and MW3, Phycicoccus sp. strain MW4 and Nocardioides sp. strain MW5. Our research provides the first insight into the metabolism of ritalinic acid and suggests that it may differ depending on the strain and growth conditions, especially on availability of nitrogen. The isolates obtained in this study can serve as model organisms in further studies on the catabolism of ritalinic acid and methylphenidate but potentially also other compounds with similar structures. Our findings have important implication for the sewage epidemiology. We demonstrated that ritalinic acid is subject to quick and efficient biodegradation thus its use as a stable biomarker should be reconsidered.