@article {740,
	title = {Synthetic mimic of antimicrobial peptide with nonmembrane-disrupting antibacterial properties.},
	journal = {Biomacromolecules},
	volume = {9},
	year = {2008},
	month = {2008 Nov},
	pages = {2980-3},
	abstract = {Polyguanidinium oxanorbornene ( PGON) was synthesized from norbornene monomers via ring-opening metathesis polymerization. This polymer was observed to be strongly antibacterial against Gram-negative and Gram-positive bacteria as well as nonhemolytic against human red blood cells. Time-kill studies indicated that this polymer is lethal and not just bacteriostatic. In sharp contrast to previously reported SMAMPs (synthetic mimics of antimicrobial peptides), PGON did not disrupt membranes in vesicle-dye leakage assays and microscopy experiments. The unique biological properties of PGON, in same ways similar to cell-penetrating peptides, strongly encourage the examination of other novel guanidino containing macromolecules as powerful and selective antimicrobial agents.},
	keywords = {Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Erythrocytes, Gram-Negative Bacteria, Gram-Positive Bacteria, Guanidines, Humans, Microbial Sensitivity Tests, Molecular Mimicry, Polymers},
	issn = {1526-4602},
	doi = {10.1021/bm800855t},
	author = {Gabriel, Gregory J and Madkour, Ahmad E and Dabkowski, Jeffrey M and Nelson, Christopher F and N{\"u}sslein, Klaus and Tew, Gregory N}
}
@article {744,
	title = {Salinity constraints on subsurface archaeal diversity and methanogenesis in sedimentary rock rich in organic matter.},
	journal = {Appl Environ Microbiol},
	volume = {73},
	year = {2007},
	month = {2007 Jul},
	pages = {4171-9},
	abstract = {The diversity of microorganisms active within sedimentary rocks provides important controls on the geochemistry of many subsurface environments. In particular, biodegradation of organic matter in sedimentary rocks contributes to the biogeochemical cycling of carbon and other elements and strongly impacts the recovery and quality of fossil fuel resources. In this study, archaeal diversity was investigated along a salinity gradient spanning 8 to 3,490 mM Cl(-) in a subsurface shale rich in CH(4) derived from biodegradation of sedimentary hydrocarbons. Shale pore waters collected from wells in the main CH(4)-producing zone lacked electron acceptors such as O(2), NO(3)(-), Fe(3+), or SO(4)(2-). Acetate was detected only in high-salinity waters, suggesting that acetoclastic methanogenesis is inhibited at Cl(-) concentrations above approximately 1,000 mM. Most-probable-number series revealed differences in methanogen substrate utilization (acetate, trimethylamine, or H(2)/CO(2)) associated with chlorinity. The greatest methane production in enrichment cultures was observed for incubations with salinity at or close to the native pore water salinity of the inoculum. Restriction fragment length polymorphism analyses of archaeal 16S rRNA genes from seven wells indicated that there were links between archaeal communities and pore water salinity. Archaeal clone libraries constructed from sequences from 16S rRNA genes isolated from two wells revealed phylotypes similar to a halophilic methylotrophic Methanohalophilus species and a hydrogenotrophic Methanoplanus species at high salinity and a single phylotype closely related to Methanocorpusculum bavaricum at low salinity. These results show that several distinct communities of methanogens persist in this subsurface, CH(4)-producing environment and that each community is adapted to particular conditions of salinity and preferential substrate use and each community induces distinct geochemical signatures in shale formation waters.},
	keywords = {Archaea, Base Sequence, Cloning, Molecular, DNA Primers, Genes, Archaeal, Genetic Variation, Geologic Sediments, Methane, Michigan, Molecular Sequence Data, Organic Chemicals, Phylogeny, RNA, Archaeal, RNA, Ribosomal, 16S, Sodium Chloride, Soil, Soil Microbiology, Water Microbiology},
	issn = {0099-2240},
	doi = {10.1128/AEM.02810-06},
	author = {Waldron, Patricia J and Petsch, Steven T and Martini, Anna M and N{\"u}sslein, Klaus and N{\"u}slein, Klaus}
}
@article {751,
	title = {Shifts in rhizoplane communities of aquatic plants after cadmium exposure.},
	journal = {Appl Environ Microbiol},
	volume = {71},
	year = {2005},
	month = {2005 May},
	pages = {2484-92},
	abstract = {In this study we present the comparative molecular analysis of bacterial communities of the aquatic plant Lemna minor from a contaminated site (RCP) and from a laboratory culture (EPA), as well as each of these with the addition of cadmium. Plants were identified as L. minor by analysis of the rpl16 chloroplast region. Comparative bacterial community studies were based on the analyses of 16S rRNA clone libraries, each containing about 100 clones from the root surfaces of plants. Bacterial communities were compared at three phylogenetic levels of resolution. At the level of bacterial divisions, differences in diversity index scores between treatments, with and without cadmium within the same plant type (EPA or RCP), were small, indicating that cadmium had little effect. When we compared genera within the most dominant group, the beta-proteobacteria, differences between unamended and cadmium-amended libraries were much larger. Bacterial diversity increased upon cadmium addition for both EPA and RCP libraries. Analyses of diversity at the phylotype level showed parallel shifts to more even communities upon cadmium addition; that is, percentage changes in diversity indices due to cadmium addition were the same for either plant type, indicating that contamination history might be independent of disturbance-induced diversity shifts. At finer phylogenetic levels of resolution, the effects of cadmium addition on bacterial communities were very noticeable. This study is a first step in understanding the role of aquatic plant-associated microbial communities in phytoremediation of heavy metals.},
	keywords = {Araceae, Bacteria, Base Sequence, Cadmium, Molecular Sequence Data, Phylogeny, Plant Roots, RNA, Ribosomal, 16S},
	issn = {0099-2240},
	doi = {10.1128/AEM.71.5.2484-2492.2005},
	author = {Stout, Lisa M and N{\"u}sslein, Klaus}
}
@article {750,
	title = {Simple oligomers as antimicrobial peptide mimics.},
	journal = {J Ind Microbiol Biotechnol},
	volume = {32},
	year = {2005},
	month = {2005 Jul},
	pages = {296-300},
	abstract = {New approaches to antibiotic design are desperately needed. The design of simple oligomers that capture the shape and biological function of natural antimicrobial peptides could prove to be versatile and highly successful. We discuss the use of aromatic backbones to design facially amphiphilic (FA) beta-sheet like structures which are potently antimicrobial. These oligomers capture the physiochemical properties of peptides like the Magainins and Defensins, which fold into specific conformations that are amphiphilic resulting in antimicrobial activity. However, natural peptides are expensive to prepare and difficult to produce on large scale. The design of polymers and oligomers that mimic the complex structures and remarkable biological properties of proteins is an important endeavor and provides attractive alternatives to the difficult synthesis of natural peptides. We therefore have designed a series of FA oligomers that are easy to prepare from inexpensive monomers. They adopt structures very reminiscent of amphiphilic beta-sheets and have significant activity with minimal inhibitory concentrations at 6 h in the low microgram per ml range (muM to nM). They are active against a broad spectrum of bacteria including gram-positive and gram-negative as well as antibiotic resistant strains.},
	keywords = {Amides, Anti-Bacterial Agents, Antimicrobial Cationic Peptides, Drug Resistance, Bacterial, Gram-Negative Bacteria, Gram-Positive Bacteria, Inhibitory Concentration 50, Peptides, Protein Conformation},
	issn = {1367-5435},
	doi = {10.1007/s10295-005-0219-0},
	author = {Rennie, Jason and Arnt, Lachelle and Tang, Haizhong and N{\"u}sslein, Klaus and Tew, Gregory N}
}
