Yen NTN, Chung DD, Hong NTK, Cham NP, Nhan VT, Linh DTL, Ngoc NLB, Thai NM, Nga ND, Anh NT. 2023. Isolation, phylogenetic analysis and bioprospection of myxobacteria from Vietnam. Biodiversitas 24: 5653-5663. Myxobacteria have been considered microbial factories for producing secondary metabolites that have a variety of potential biological actions for discovering and isolating new biological molecules. Myxobacteria were isolated from soil samples collected in some provinces/cities in Vietnam. The purified isolates were identified based on morphology, biochemical test and phylogenetic analysis inferred from 16S rRNA gene. High-throughput screening assays including 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DDPH) for antioxidant properties and microdilution for antimicrobial activity were performed with myxobacterial extracts. Compounds from potential strain were predicted using liquid chromatography coupled with mass spectrometry. Forty-three myxobacterial strains were isolated and classified into seven genera of Angiococcus, Archangium, Chondromyces, Corallococcus, Cystobacter, Melittangium, and Myxococcus. The extract from CT21 strain had the highest total antioxidant activity (IC50 = 52.34 ± 1.47 and 30.28 ± 0.74 ?g/mL for the DPPH and ABTS, respectively). It is worth noting that all strains isolated myxobacterial strains show inhibitory activity against at least one of the tested microorganisms. The most potent antimicrobial strain was Myxococcus stipitatus GL41, which inhibited all tested microorganisms, and the minimal inhibitory concentration (MIC) values were 1 ?g/mL against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive Staphylococcus aureus (MSSA), Streptococcus faecalis, Candida albicans, and Aspergillus niger. Mass spectrometry analysis revealed the presence of althiomycin - the polyketide antibiotic from ethyl acetate fraction. In the present study, myxobacteria were isolated from soil sample collected from Vietnam, analyzed phylogenetically, and screened for biological activities.

Mục tiêu: Khảo sát ảnh hưởng của tình trạng viêm âm đạo (VAĐ), việc sử dụng thuốc đến hiệu quả điều trị VAĐ, khảo sát kiến thức, thái độ, hành vi của bệnh nhân (BN) điều trị ngoại trú tại Bệnh viện Đa khoa vùng Tây Nguyên. Phương pháp nghiên cứu: Nghiên cứu mô tả cắt ngang dựa trên hồ sơ bệnh án và bảng trả lời câu hỏi của 186 BN được chẩn đoán VAĐ trong 350 phụ nữ đến khám từ tháng 12/2020 - 5/2022. Kết quả: Tác nhân gây bệnh là nấm Candida (46,8%), vi khuẩn (46,2%), nhiễm kết hợp vi khuẩn + nấm (7%). Sự phối hợp 2 thuốc gồm thuốc đặt + dùng ngoài (46,2%), nhóm thuốc kháng nấm (54,8%), tỷ lệ phối hợp giữa thuốc kháng sinh - kháng nấm (72,6%). Có mối liên quan giữa tuổi, tình trạng hôn nhân với tỷ lệ VAĐ có ý nghĩa thống kê. BN có kiến thức, thái độ, hành vi đúng về VAĐ lần lượt là 51,7%, 53,7% và 51,1%. Kết luận: Cần tăng cường chỉ định xét nghiệm, sử dụng thuốc hợp lý, giáo dục nâng cao kiến thức, thái độ và hành vi của phụ nữ về VAĐ.

The abnormal accumulation of alpha-synuclein (α-syn) is a core pathogenic mechanism in Parkinson’s disease. The nanobody PFFNB2 inhibits α-syn pre-formed fibrils (α-syn PFF) but faces expression challenges due to the absence of a canonical disulfide bond. This study aimed to express PFFNB2 and α-syn in the periplasm of Escherichia coli (E. coli) W3110 and its ompC-deficient mutant (∆ompC). PFFNB2 was expressed with and without a Maltose Binding Protein (MBP) fusion tag, while α-syn was expressed tag-free. Periplasmic proteins were extracted via osmotic shock, purified using chromatography, and analyzed for molecular weight and expression yield. The amyloid fibril-forming capacity of α-syn was evaluated using a Thioflavin T assay, and apparent binding potency was assessed via ELISA. Results demonstrated successful cloning, expression, and purification of both proteins. MBP-PFFNB2 yielded higher expression yield than the MBP-free form. Although the ∆ompC mutant showed a lower nanobody expression yield than the wild-type strain, the MBP-PFFNB2 obtained from this mutant exhibited optimal activity and specifically bound to α-syn PFF (EC₅₀ of 0.3445 nM). Regarding α-syn, the ∆ompC mutant provided a superior expression yield, and lactose induction significantly reduced the formation of toxic oligomeric forms. In conclusion, combining periplasmic expression, an MBP fusion tag, and the E. coli W3110 ∆ompC strain creates a potential system for producing PFFNB2 nanobodies with high anti-α-syn PFF activity.

It's amazing how natural soap is everywhere and ready to use. With this discovery, everyone – even humans in remote places – has access to soap – an effective weapon against countless dangerous enemies in nature such as bacteria, viruses. , parasites...

Acinetobacter baumannii is the leading cause of hospital-acquired infection in Vietnam. Of note, antibiotic resistance genes are significantly popular in clinical isolates of A. baumannii . Therefore, rapid identification of A. baumannii and determination of antibiotic resistance genes will help to make effective clinical decisions related to antibiotic use. This paper proposes a multiplex PCR to identify Acinetobacter baumannii and detect their ß-lactam antibiotic resistance genes in clinical isolates. Multiplex PCR was applied to amplified rec A gene and region ITS 16S - 23S rDNA for Rapid detection of A. baumannii. The two antibiotic resistance genes - bla _OXA-51-like , amp C gene - were detected by multiplex PCR and three genes coding Extended-spectrum beta-lactamases - bla _CTX-M , bla _TEM , bla _SHV genes - were subjected to PCR. 49 bacteria strains were subjected to colony PCR. The result showed that 46 strains were A. baumannii and 3 strains belonged to the genus Acinetobacter. The multiplex PCR showed that all of 46 A. baumannii containing the bla _OXA-51-like gene and the Amp C gene; 34 strains possess the gene bla _TEM and none of them has bla _CTX-M and bla _SHV genes. The results of the multiplex PCR are the same as those of the in vitro antibiotic sensitivity testing of A. baumannii . However, applying the multiplex PCR directly from the bacteria colony, we can proceed simultaneously with the bacterial identification and the antibiotic resistance gene detection. Highlights: 100% of isolates of A. baumannii contains the bla _OXA-51-like gene and the Amp C gene. 34/46 isolates possess the gene bla _TEM , however, do not contain bla _CTX-M and bla _SHV genes. Combined disc test with cefotaxime/clavulanic acid/boronic acid is an excellent method to analyse ESBL phenotype.