Hasil untuk "Biotechnology"

M. Harmsen, H. de Haard

Camelids produce functional antibodies devoid of light chains of which the single N-terminal domain is fully capable of antigen binding. These single-domain antibody fragments (VHHs or Nanobodies®) have several advantages for biotechnological applications. They are well expressed in microorganisms and have a high stability and solubility. Furthermore, they are well suited for construction of larger molecules and selection systems such as phage, yeast, or ribosome display. This minireview offers an overview of (1) their properties as compared to conventional antibodies, (2) their production in microorganisms, with a focus on yeasts, and (3) their therapeutic applications.

P. Bosland, E. Votava

A. Banerjee, Rohit Sharma, Y. Chisti et al.

V. Lozinsky, I. Galaev, F. Plieva et al.

D. Pires, H. Oliveira, Luís D. R. Melo et al.

Bacteriophages (phages), natural enemies of bacteria, can encode enzymes able to degrade polymeric substances. These substances can be found in the bacterial cell surface, such as polysaccharides, or are produced by bacteria when they are living in biofilm communities, the most common bacterial lifestyle. Consequently, phages with depolymerase activity have a facilitated access to the host receptors, by degrading the capsular polysaccharides, and are believed to have a better performance against bacterial biofilms, since the degradation of extracellular polymeric substances by depolymerases might facilitate the access of phages to the cells within different biofilm layers. Since the diversity of phage depolymerases is not yet fully explored, this is the first review gathering information about all the depolymerases encoded by fully sequenced phages. Overall, in this study, 160 putative depolymerases, including sialidases, levanases, xylosidases, dextranases, hyaluronidases, peptidases as well as pectate/pectin lyases, were found in 143 phages (43 Myoviridae, 47 Siphoviridae, 37 Podoviridae, and 16 unclassified) infecting 24 genera of bacteria. We further provide information about the main applications of phage depolymerases, which can comprise areas as diverse as medical, chemical, or food-processing industry.

M. Siso

U. Hölker, M. Höfer, J. Lenz

G. Walsh

L. C. Tan, Y. Nancharaiah, E. V. van Hullebusch et al.

V. Kalia, S. Patel, Y. Kang et al.

The mechanisms through which microbes communicate using signal molecules has inspired a great deal of research. Microbes use this exchange of information, known as quorum sensing (QS), to initiate and perpetuate infectious diseases in eukaryotic organisms, evading the eukaryotic defense system by multiplying and expressing their pathogenicity through QS regulation. The major issue to arise from such networks is increased bacterial resistance to antibiotics, resulting from QS-dependent mediation of the formation of biofilm, the induction of efflux pumps, and the production of antibiotics. QS inhibitors (QSIs) of diverse origins have been shown to act as potential antipathogens. In this review, we focus on the use of QSIs to counter diseases in humans as well as plants and animals of economic importance. We also discuss the challenges encountered in the potential applications of QSIs.

S. Ståhl, T. Gräslund, A. Eriksson Karlström et al.

D. Johnson

J. Alegre, K. Sengupta, R. Lapiedra

R. J. Bothast, M. Schlicher

F. Engelmann

Liliam K Harada, Erica C Silva, Welida F. Campos et al.

Bacteriophage particles are the most abundant biological entities on our planet, infecting specific bacterial hosts in every known environment and being major drivers of bacterial adaptive evolution. The study of bacteriophage particles potentially sheds light on the development of new biotechnology products. Bacteriophage therapy, although not new, makes use of strictly lytic phage particles as an alternative in the antimicrobial treatment of resistant bacterial infections and is being rediscovered as a safe method due to the fact that these biological entities devoid of any metabolic machinery do not have affinity to eukaryotic cells. Furthermore, bacteriophage-based vaccination is emerging as one of the most promising preventive strategies. This review paper discusses the biological nature of bacteriophage particles, their mode(s) of action and potential exploitation in modern biotechnology. Topics covered in detail include the potential of bacteriophage particles in human infections (bacteriophage therapy), nanocages for gene delivery, food biopreservation and safety, biocontrol of plant pathogens, phage display, bacterial biosensing devices, vaccines and vaccine carriers, biofilm and bacterial growth control, surface disinfection, corrosion control, together with structural and functional stabilization issues.

Anne Pohlmann, W. F. Fricke, F. Reinecke et al.

The H2-oxidizing lithoautotrophic bacterium Ralstonia eutropha H16 is a metabolically versatile organism capable of subsisting, in the absence of organic growth substrates, on H2 and CO2 as its sole sources of energy and carbon. R. eutropha H16 first attracted biotechnological interest nearly 50 years ago with the realization that the organism's ability to produce and store large amounts of poly[R-(–)-3-hydroxybutyrate] and other polyesters could be harnessed to make biodegradable plastics. Here we report the complete genome sequence of the two chromosomes of R. eutropha H16. Together, chromosome 1 (4,052,032 base pairs (bp)) and chromosome 2 (2,912,490 bp) encode 6,116 putative genes. Analysis of the genome sequence offers the genetic basis for exploiting the biotechnological potential of this organism and provides insights into its remarkable metabolic versatility.

K. Dumorné, David Isidoro Camacho Córdova, Marcia Astorga-Eló et al.

Sara Pearl, Anand Anbarasu

Abstract Acinetobacter baumannii (A. baumannii) is a major multidrug-resistant pathogen, posing serious threats in the healthcare settings. This study provides a comprehensive genomic analysis of nosocomial A. baumannii whole-genome sequences retrieved from NCBI Genome database. Multilocus sequence typing and capsule typing were performed to investigate the clonal diversity. The genomes were characterized to identify antimicrobial resistance genes (ARGs), virulence factors, and mobile genetic elements. Further, pangenome analysis was conducted to examine the core and accessory genomes of A. baumannii. Our dataset comprised of 609 genomes deposited from diverse geographic regions worldwide between 2004 and 2024. The genomes showed high clonal heterogeneity, with sequence type ST2 being the predominant sequence type. A total of 185 unique ARGs were identified, with majority of them associated with efflux pump and β-lactamase coding genes. Over 25,000 IS elements were detected, with IS4 family being the prevalent type. High abundance of integron-mediated resistance determinants, especially for aminoglycosides and β-lactams, were identified. The open pangenome window due to its larger accessory genome suggested substantial genome plasticity. Our findings highlight A. baumannii’s rapid evolution and resistance potential, emphasizing need for alternative therapeutic strategies. Enhanced surveillance, infection control measures, and antimicrobial stewardship are crucial to combat this persistent threat.

Yi Liu, Yitong Liu, Jingchao Hu et al.

Abstract Periodontitis causes the destruction of tooth-supporting tissues, and current therapies for periodontal regeneration are invasive. In this study, a human dental pulp stem cell (DPSC; hDP-MSC) injection was developed to promote periodontal regeneration through a non-invasive procedure. A total of 132 patients with chronic periodontitis (158 teeth) from two centers in China were included. Thirty-six were randomly assigned to different DPSC dose groups (ranging from 1 × 106 to 1 × 107 DPSCs per tooth, with nine injected with saline only), and 96 were randomly assigned to a single-injection group (1 × 107/0.6 mL DPSCs), a double-injection group (1 × 107/0.6 mL DPSCs × 2), or a saline group, in a 1:1:1 ratio. At 6 months post-therapy, attachment loss (AL), periodontal probing depth (PD), gingival recession (GR), tooth mobility (TM), and bone defect depth (BDD) were examined. The primary outcome was AL. DPSC injection resulted in greater improvement in BDD (0.30 ± 0.484 mm) compared to saline injection (0.04 ± 0.315 mm). Post hoc analysis showed that DPSC injection had significantly better outcomes in patients with stage III periodontitis (AL ≥ 5 mm): 54 patients received DPSCs, and 40 received saline. AL improved by 1.67 ± 1.508 mm in the DPSC group (26.81% improvement) and by 1.03 ± 1.310 mm in the saline group (17.43% improvement). The therapeutic effects encompassed improvements in both soft and hard tissues. In summary, DPSC injection was safe and improved clinical outcomes compared to saline injection in patients with stage III periodontitis. Larger trials are warranted to validate these findings (ClinicalTrials.gov registration: NCT05924373).