The unrestricted use of natural antibiotics and their analogues leads to the spread of infections caused by antibiotic-resistant strains of pathogens. This has presented major challenges for antibiotic discovery. Screening of natural products from extremophiles offers a significantly higher potential for discovering antimicrobial activity. A significant portion of the Earth’s biosphere is found in perennially cold environments including the deep ocean. However, little is known about the diversity and function of icy microbial communities. Thus, recent work has focused more on psychrophiles living in ice and deep sea, in turn, to search for new natural antibiotics.

The discovery of new psychrophiles and the high-throughput technologies for screening for new cold-active antibiotics has had a great impact on the field of industrial bioconversions. Since the early pioneering days of discovery of novel antibiotics from deep marine psychrophiles, microorganisms are still often routinely used as sources of potential novel antibiotics, but progress is impeded by our inability to isolate pure cultures.

This Special Issue aims to create an interdisciplinary platform addressing the discovery of antibiotics from deep marine psychrophiles focused on the screening of deep marine psychrophiles, culture-dependent techniques to proceed to functional genomics, physiology and metagenomics constitution for the gene of interest involved in the induction and repression in antibiotic synthesis. In addition, we aim to identify the importance of the whole-genome sequencing methods as a challenging research domain with great potential for the discovery of new deep marine cold-active antibiotics. We welcome original research articles (in silico, in vitro, and in vivo) and review articles that will illustrate and stimulate the importance of natural antibiotics from deep marine psychrophiles for next-generation drug discovery.

Potential topics include but are not limited to the following:

• Identification of new antibiotics from marine psychrophiles
• Novel methodologies and technologies with potential applications for cold-active antibiotics
• Screening for genes of interest involved in the antibiotic synthesis from archives and metagenomic libraries
• Directed selection techniques and genetic engineering methods of antibiotic-producing marine psychrophiles for new hybrid antibiotic synthesis (for manipulation of biosynthetic pathways)
• Development of static approaches to enhance the production in downstream processing
• A combination of analysis and tandem separation techniques for antibiotics from marine psychrophiles (high-performance liquid chromatography coupled with mass spectrometry or nuclear magnetic resonance spectroscopy)