A taxonomic study was performed on strain YIM 31775T, which was isolated from a soil sample collected from Yunnan Province, China. The isolate was chemo-organotrophic, aerobic and Gram-negative. Cells were short rods and motile, with one or more polar flagella. Growth temperature and pH ranged from 4 to 55 °C and 6·5 to 12·0, respectively; the optimum growth temperature and pH were 28–37 °C and 7·0–9·0, respectively. Q-8 was the predominant respiratory lipoquinone. The major fatty acids were C16 : 1 ω7c (42·4 %) and C16 : 0 (28·1 %). The DNA G+C content was 62·4±0·3 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain YIM 31775T should be placed within the family ‘Oxalobacteraceae’, in which it formed a distinct lineage. Based on the high 16S rRNA gene sequence divergence and phenotypic characteristics, it is proposed that strain YIM 31775T should be classified as representing a novel member of the family ‘Oxalobacteraceae’, for which the name Naxibacter alkalitolerans gen. nov., sp. nov. is proposed. The type strain is YIM 31775T (=CCTCC AA 204003T=KCTC 12194T).

A Gram-positive, motile, short-rod-shaped strain, designated YIM 004T, was isolated from a forest-soil sample collected from Lijiang, Yunnan Province, China, and was investigated using a polyphasic taxonomic approach. The isolate contained chemotaxonomic markers that corresponded to those of its phylogenetic neighbour, Georgenia muralis, i.e. it possessed peptidoglycan type A4α with lysine as the diagnostic cell-wall diamino acid, the predominant menaquinone was MK-8(H4) and the major fatty acid was ai-C15 : 0. The G+C content of the genomic DNA was 72.9 mol%. Strain YIM 004T exhibited a 16S rRNA gene sequence similarity of 97.3 % and a DNA–DNA relatedness value of 18 % with respect to G. muralis DSM 14418T. On the basis of the phenotypic and genotypic differences between the isolate and G. muralis, strain YIM 004T represents a novel species of the genus Georgenia, for which the name Georgenia ruanii sp. nov. is proposed. The type strain is YIM 004T (=CCTCC AB 204065T=DSM 17458T=KCTC 19029T). In addition, an emended description of the genus Georgenia is presented.

Endophytic actinobacteria, which exist in the inner tissues of living plants, have attracted increasing attention among taxonomists, ecologists, agronomists, chemists and evolutionary biologists. Numerous studies have indicated that these prolific actinobacteria appear to have a capacity to produce an impressive array of secondary metabolites exhibiting a wide variety of biological activity, such as antibiotics, antitumor and anti-infection agents, plant growth promoters and enzymes, and may contribute to their host plants by promoting growth and enhancing their ability of withstanding the environmental stresses. These microorganisms may represent an underexplored reservoir of novel species of potential interest in the discovery of novel lead compounds and for exploitation in pharmaceutical, agriculture and industry. This review focuses on new findings in the isolation methods, bio- and chemical diversity of endophytic actinobacteria and reveals the potential biotechnological application. The facing problems and strategies for biodiversity research and bioactive natural products producing are also discussed.

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A Gram-positive, non-motile, white-pigmented, short rod actinobacterium, designated YIM 90734 T , was isolated from a saline soil sample collected from Ganjiahu Suosuo Forest National Nature Reserve in Xinjiang province, north-west China, and its taxonomic position was investigated by using a polyphasic approach. Strain YIM 90734 T grew optimally at 28-37 6C and pH 6.0-8.0 and in 5 % (w/v) NaCl. The peptidoglycan type was A4a, L-Lys-L-Ala-L-Glu and tyvelose and mannose were the major cell-wall sugars. The predominant menaquinones were MK-10 and MK-9. Major cellular fatty acids (.10 % of total) were anteiso-C 15 : 0 and anteiso-C 17 : 0 . The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown phospholipid and two unknown glycolipids. The DNA G+C content was 70.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 90734 T belonged to the genus Zhihengliuella. The 16S rRNA gene sequence similarity between strain YIM 90734 T and the type strain of the only recognized Zhihengliuella species, Zhihengliuella halotolerans, was 97.7 %. However, the level of DNA-DNA relatedness of the two strains was 41.4 %. The DNA-DNA relatedness data and differential phenotypic properties, together with the phylogenetic distinctiveness, demonstrated that strain YIM 90734 T could be differentiated from Z.halotolerans. On the basis of the data presented, strain YIM 90734 T is considered to represent a novel species of the genus Zhihengliuella, for which the name Zhihengliuella alba sp. nov. is proposed. The type strain is YIM 90734 T (5KCTC 19375 T 5DSM 21143 T ). The description of the genus Zhihengliuella has also been emended. et al. (2007) and initially contained only one species, Zhihengliuella halotolerans (type strain YIM 70185 T ), which was isolated from Qinghai province, north-west China. The genus Zhihengliuella is described as comprising a Grampositive, non-motile, short-rod actinobacterium that was catalase-positive and oxidase-negative. The peptidoglycan type was A4a, L-Lys-L-Ala-L-Glu. Cell-wall sugars contained tyvelose and glucose. The predominant menaquinones were MK-9 and MK-10 and the major fatty acids were anteiso-C 15 : 0 and iso-C 15 : 0 . The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol and phosphatidylinositol. The G+C content of the genomic DNA was about 66.5 mol% . In this paper, we describe the characterization and classification of a halotolerant actinobacterium, designated YIM 90734 T , which was isolated from a saline sample collected from Ganjiahu Suosuo Forest National Nature Reserve in Xinjiang province, north-west China and was considered to represent a novel species of the genus Zhihengliuella. The genus Zhihengliuella was first established by Zhang Strain YIM 90734T was isolated from a saline soil sample after 3 weeks incubation at 37 u C on modified ISP 5 medium comprising (1 21 distilled water, final pH 7.5): 1 g L-asparagine, 10 g glycerol, 5 g yeast extract, 1 g K 2 HPO 4 , 5 g KNO 3 , 100 g NaC...

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The evolution of mobile malware poses a serious threat to smartphone security. Today, sophisticated attackers can adapt by maximally sabotaging machine-learning classifiers via polluting training data, rendering most recent machine learning-based malware detection tools (such as Drebin, DroidAPIMiner, and MaMaDroid) ineffective. In this paper, we explore the feasibility of constructing crafted malware samples; examine how machine-learning classifiers can be misled under three different threat models; then conclude that injecting carefully crafted data into training data can significantly reduce detection accuracy. To tackle the problem, we propose KuafuDet, a two-phase learning enhancing approach that learns mobile malware by adversarial detection. KuafuDet includes an offline training phase that selects and extracts features from the training set, and an online detection phase that utilizes the classifier trained by the first phase. To further address the adversarial environment, these two phases are intertwined through a self-adaptive learning scheme, wherein an automated camouflage detector is introduced to filter the suspicious false negatives and feed them back into the training phase. We finally show that KuafuDet can significantly reduce false negatives and boost the detection accuracy by at least 15%. Experiments on more than 250,000 mobile applications demonstrate that KuafuDet is scalable and can be highly effective as a standalone system.

A novel yellow-pigmented, non-motile, non-sporulating, catalase- and oxidase-positive, obligately aerobic, moderately halophilic, facultatively alkaliphilic Gram-positive coccus, strain YIM Y15T, was isolated from a brine sample from a salt mine in Yunnan, south-west China. Strain YIM Y15T grew in the presence of 0.5–25 % (w/v) NaCl and at pH 6.0–10.0, with optimum growth at 8–10 % (w/v) NaCl and pH 8.0. It grew at 4–45 °C, with optimum growth at 37.0 °C. The major cellular fatty acids were anteiso-C15 : 0 and iso-C15 : 0. Menaquinone 6 (MK-6) was the major respiratory quinone. The cell wall contained Lys and Gly. The DNA G+C content was 46.2 mol%. Phylogenetic analyses based on 16S rRNA gene sequence comparisons revealed that strain YIM Y15T was a member of the genus Salinicoccus, with low 16S rRNA gene sequence similarity to the type strains of the five described species of the genus, Salinicoccus alkaliphilus JCM 11311T (sequence similarity 96.0 %), Salinicoccus roseus DSM 5351T (94.9 %), Salinicoccus jeotgali KCTC 13030T (94.8 %), Salinicoccus salsiraiae LMG 22840T (94.8 %) and Salinicoccus hispanicus DSM 5352T (94.7 %). Together with the phenotypic differences, these results supported the proposal of a novel species of the genus Salinicoccus, Salinicoccus kunmingensis sp. nov., with YIM Y15T (=DSM 17847T =CGMCC 1.6302T) as the type strain.