From a practical standing point, the health and well-being of

honeybees is of considerable concern as they are the important agricultural resources. Actinomycete-produced organic compounds have been marketed or learn more are being investigated as insecticides (e.g. spinosad). Given the specificity of the actinomycetes that honeybees retain in their guts and bring back to hives, several important questions have arisen: Are they beneficial bacteria or opportunistic pathogens to the honeybees? Are phenazines virulence factors or contributors to a healthy gut microbial community? Are phenazines present in raw honey and do they contribute to its antimicrobial properties? Phenazines are often produced in large quantities in situ and can be directly detected in the soil or the human tissues colonized with the microorganisms (Wilson et al., 1988; Thomashow et al., 1990). Future investigations may open new avenues for discovering new antibiotics in human medicine or exploring methods to fight honeybee diseases. We thank beekeepers John McGovern,

Edward Newman and Dr Scott Moody for providing the honeybees and for continuous support. We are grateful to Dr Kelly Johnson for helpful discussion. This project was supported by start-up funds from Ohio University to S.C. “
“Human milk contains about 7% lactose and 1% human milk oligosaccharides (HMOs) consisting of lactose with linked fucose, N-acetylglucosamine and sialic acid. In infant formula, galactooligosaccharides (GOSs) are added to replace HMOs. This study investigated the ability of six strains of lactic acid Gemcitabine bacteria (LAB), Lactobacillus acidophilus, Lactobacillus

plantarum, Lactobacillus fermentum, Lactobacillus reuteri, Streptococcus thermophilus and Leuconostoc mesenteroides subsp. cremoris, to digest HMO components, defined HMOs, and GOSs. All strains grew on lactose and glucose. N-acetylglucosamine utilization varied between strains and was maximal in L. plantarum; fucose utilization was low Fossariinae or absent in all strains. Both hetero- and homofermentative LAB utilized N-acetylglucosamine via the Embden–Meyerhof pathway. Lactobacillus acidophilus and L. plantarum were the most versatile in hydrolysing pNP analogues and the only strains releasing mono- and disaccharides from defined HMOs. Whole cells of all six LAB hydrolysed oNP-galactoside and pNP-galactoside indicating β-galactosidase activity. High β-galactosidase activity of L. reuteri, L. fermentum, S. thermophilus and L. mesenteroides subsp. cremoris whole cells correlated to lactose and GOS hydrolysis. Hydrolysis of lactose and GOSs by heterologously expressed β-galactosidases confirmed that LAB β-galactosidases are involved in GOS digestion. In summary, the strains of LAB used were not capable of utilizing complex HMOs but metabolized HMO components and GOSs. Human milk contains about 7% lactose and 1% human milk oligosaccharides (HMOs) of complex composition.