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1.  Bacteriophage prehistory 
Bacteriophage  2011;1(3):174-178.
We identified 30 actual or presumptive “bacteriophage” references dating between the years 1895 and 1917 and have further explored one of the oldest: Hankin's 1896 study of a bactericidal action associated with the waters of the Ganges and Jumna rivers in India. As Hankin's work took place approximately 20 years prior to the actual discovery of bacteriophages, no claims were made as to a possible phage nature of the phenomenon. Here we suggest that it may be imprudent to assume nevertheless that it represents an early observation of phagemediated bactericidal activity. Our principal argument is that the antibacterial aspect of these river waters was able to retain full potency following “heating” for one-half hour in hermetically sealed tubes, where heating in “open” tubes resulted in loss of antibacterial activity. We also suggest that environmental phage counts would have had to have been unusually high—greater than 106/ml impacting a single host strain—to achieve the rates of bacterial loss that Hankin observed.
PMCID: PMC3225782  PMID: 22164351
Ganges River; history; natural bactericidal activity; presumptive early phage references
2.  Facilitation of CRISPR adaptation 
Bacteriophage  2011;1(3):179-181.
CRISPR systems, as bacterial defenses against phages, logically must display in their functioning a sequence of at least three major steps. These, in order of occurrence, are “facilitation,” adaptation and interference, where the facilitation step is the main issue considered in this commentary. Interference is the blocking of phage infections as mediated in part by CRISPR spacer sequences. Adaptation, at least as narrowly defined, is the acquisition of these spacer sequences by CRISPR loci. Facilitation, in turn and as defined here, corresponds to phage-naïve bacteria avoiding death follow first-time exposure to specific phages, where bacterial survival of course is necessary for subsequent spacer acquisition. Working from a variety of perspectives, I argue that a requirement for facilitation suggests that CRISPR systems may play secondary rather than primary roles as bacterial defenses, particularly against more virulent phages. So considered, the role of facilitation in CRISPR functioning could be viewed as analogous to the building, in vertebrate animals, of adaptive immunity upon an immunological foundation comprised of mechanisms that are both more generally acting and innate.
PMCID: PMC3225783  PMID: 22164352
adaptation; adaptive immunity; CRISPR; innate immunity; restriction-modification
3.  Pros and cons of phage therapy 
Bacteriophage  2011;1(2):111-114.
Many publications list advantages and disadvantages associated with phage therapy, which is the use of bacterial viruses to combat populations of nuisance or pathogenic bacteria. The goal of this commentary is to discuss many of those issues in a single location. In terms of “Pros,” for example, phages can be bactericidal, can increase in number over the course of treatment, tend to only minimally disrupt normal flora, are equally effective against antibiotic-sensitive and antibiotic-resistant bacteria, often are easily discovered, seem to be capable of disrupting bacterial biofilms, and can have low inherent toxicities. In addition to these assets, we consider aspects of phage therapy that can contribute to its safety, economics, or convenience, but in ways that are perhaps less essential to the phage potential to combat bacteria. For example, autonomous phage transfer between animals during veterinary application could provide convenience or economic advantages by decreasing the need for repeated phage application, but is not necessarily crucial to therapeutic success. We also consider possible disadvantages to phage use as antibacterial agents. These “Cons,” however, tend to be relatively minor.
PMCID: PMC3278648  PMID: 22334867
alternative medicine; antibiotics; antimicrobial drugs; biocontrol; phage therapy
4.  Phage treatment of human infections 
Bacteriophage  2011;1(2):66-85.
Phages as bactericidal agents have been employed for 90 years as a means of treating bacterial infections in humans as well as other species, a process known as phage therapy. In this review we explore both the early historical and more modern use of phages to treat human infections. We discuss in particular the little-reviewed French early work, along with the Polish, US, Georgian and Russian historical experiences. We also cover other, more modern examples of phage therapy of humans as differentiated in terms of disease. In addition, we provide discussions of phage safety, other aspects of phage therapy pharmacology, and the idea of phage use as probiotics.
PMCID: PMC3278644  PMID: 22334863
phage history; phage therapy; pharmacology; probiotics; safety; treatment of infectious disease
5.  Lysis from without 
Bacteriophage  2011;1(1):46-49.
In this commentary I consider use of the term “lysis from without” (LO) along with the phenomenon's biological relevance. LO originally described an early bacterial lysis induced by high-multiplicity virion adsorption and that occurs without phage production (here indicated as LOV). Notably, this is more than just high phage multiplicities of adsorption leading to bacterial killing. The action on bacteria of exogenously supplied phage lysin, too, has been described as a form of LO (here, LOL). LOV has been somewhat worked out mechanistically for T4 phages, has been used to elucidate various phage-associated phenomena including discovery of the phage eclipse, may be relevant to phage ecology, and, with resistance to LO (LOR), is blocked by certain phage gene products. Speculation as to the impact of LOV on phage therapy also is fairly common. Since LOV assays are relatively easily performed and not all phages are able to induce LOV, a phage's potential to lyse bacteria without first infecting should be subject to at least in vitro experimental confirmation before the LOV label is applied. The term “abortive infection” may be used more generally to describe non-productive phage infections that kill bacteria.
PMCID: PMC3109453  PMID: 21687534
abortive infection; bacteriophage; lysin; lysis; lysis from without; phage therapy

Results 1-5 (5)