Advances in Microbial Ecology

The substantial and impressive changes in microbial ecology can scarcely be chronicled in a meaningful fashion, and a review series such as Advances in Microbial Ecology can thus not do justice to the numerous studies that have been published in recent years. On the other hand, the mere existence of this series bears testimony to the many and diverse activities. The growing concern with microbial communities and processes in natural ecosystems is not restricted to scientists in one region and is not limited to particular groups of organisms or to individual theoretical or applied problems. The recent and successful international symposium on microbial ecology held in New Zealand-sponsored in part by the International Commission on Microbial Ecology, as is the Advances-and the general microbiology and ecology conferences and congresses have included reports from investigators from all corners of the globe and have explored both new and traditional areas, agricultural and public health problems, individual species and complex communities, and heterotrophs and autotrophs as well as ecosystem models relying on mathematical concepts and environmental processes needing sophisticated chemistry for their definition. The reviews in the present volume thus can offer only a minute sampling of the multitude of topics being actively explored at the present time. Two of the reviews focus attention on biogeochemical cycles regulated by microorganisms, in particular the way these organisms contribute to or control the levels and identities of chemical substances in the atmosphere. The chapter by Y. Dommergues, L. W. Belser, and E. L.

1 Principal-Components and Factor Analysis for the Description of Microbial Populations.- 1. Introduction.- 2. Adansonian Classification and Microbiology.- 3. Methods for Collecting Primary Data.- 3.1. Introduction.- 3.2. Multipoint Techniques.- 3.3. Choice of Tests.- 3.4. Data Collection and Storage.- 4. Factor Analysis for Describing Microbial Populations.- 4.1. Principal-Components Analysis and Factor Analysis.- 4.2. Mean Values for Test Variables.- 4.3. Correlation Matrix between Variables.- 4.4. Eigenvalues, Variance, and Communality.- 4.5. Rotated Factor Matrix.- 5. Applications of Factor Analysis in Environmental Microbiology.- 5.1. Introduction.- 5.2. Effect of Soil-Management Practices on Bacterial Populations.- 5.3. Effects of Chemicals on Bacterial Populations.- 6. Conclusions and Perspectives.- References.- 2 Limiting Factors for Microbial Growth and Activity in Soil.- 1. Introduction.- 1.1. Concept of the Limiting Factor.- 1.2. Application of the Limiting Factor Concept to Soil.- 1.2.1. Interactions between Environmental Factors.- 1.2.2. Alteration of the Range of Tolerance.- 1.2.3. Variations of Environmental Factors in Time and Space.- 1.2.4. Modified Concept of Limiting Factors.- 2. The Soil Habitat.- 2.1. Heterogeneous Distribution of Microorganisms in Soil.- 2.2. Heterogeneous Physical Nature of Soil Habitat.- 2.3. Microbial Diversity in Soil.- 3. Methodology for Study of Limiting Factors in Soil.- 3.1. Process Chemistry and General Microbial Indices.- 3.2. Indicators of Microbial Activity.- 3.2.1. Isotope Tracers.- 3.2.2. Acetylene Reduction.- 3.3. Indicators of General Microbial Numbers or Biomass.- 3.3.1. Direct Microscopy.- 3.3.2. Biomass Estimates by Indicator Chemical Constituents.- 3.4. Enumeration of Specific Microorganisms.- 3.4.1. Selective Media.- 3.4.2. Immunofluorescence.- 4. Major Limiting Factors.- 4.1. Energy.- 4.2. Light.- 4.2.1. Light Deficiency.- 4.2.2. Light Excess.- 4.3. Temperature.- 4.4. Water Tension.- 4.5. Oxygen.- 4.6. pH.- 4.7. Mineral Nutrients.- 4.8. Biological Factors.- 5. Factors Limiting Growth and Activity for Selected Processes.- 5.1. Nitrogen Fixation.- 5.1.1. Soil Physical-Chemical Factors Limiting Nodule Initiation.- 5.1.2. Soil Biological Factors Limiting Nodule Initiation.- 5.1.3. Intrinsic Factors Limiting the Endophyte.- 5.1.4. Prospects for Relieving Limitations to Nodule Initiation.- 5.2. Nitrification.- 5.2.1. Major Factors Limiting Nitrification.- 5.2.2. Research Approaches Needed.- 5.2.3. Nitrifier Diversity and Activity.- 5.3. Denitrification.- 5.3.1. Anaerobiosis.- 5.3.2. Energy and Electron-Yielding Substrates.- 5.3.3. Nitrate.- 5.4. Sulfate Reduction.- 5.4.1. Anaerobiosis.- 5.4.2. Energy and Electron-Yielding Substrates.- 5.4.3. Sulfate.- 5.5. Formation of Peats and Mor Horizons.- 6. Modeling Microbial Growth and Activity in Soil.- 6.1. Components of the Model.- 6.2. Operation of the Model.- 6.3. Treatment of Limiting Factors.- 6.4. The Model as an Investigative Tool.- References.- 3 Eco-Physiological Aspects of Microbial Growth in Aerobic Nutrient-Limited Environments.- 1. Introduction.- 2. Mechanisms of Adaptation to Low-Nutrient Environments.- 2.1. Regulation and Modulation of Substrate-Uptake Systems.- 2.2. Regulation of Metabolism of Nonlimiting Nutrients.- 2.3. Regulation and Modulation of Polymer Synthesis.- 2.4. Coordinated Regulation of Cell Synthesis.- 3. Bioenergetic Considerations.- 4. Transient-State Phenomena: Microbial Reactivity.- 5. Conclusions.- References.- 4 Role of Microorganisms in the Atmospheric Sulfur Cycle.- 1. Introduction.- 2. Microbial Production of Volatile Sulfur Compounds.- 3. Microbial Sources of Atmospheric Sulfur.- 3.1. Terrestrial Microorganisms.- 3.1.1. Microbial Activity in Soils.- 3.1.2. Microbial Activity in Manures.- 3.1.3. Microbial Activity in Phyllospheres and Rhizospheres.- 3.2. Aquatic Microorganisms.- 4. Microbial Sinks of Atmospheric Sulfur.- 5. Conclusions.- References.- 5 Microbiological Aspects of Regulating the Carbon Monoxide Content in the Earth’s Atmosphere.- 1. Introduction.- 2. Carbon Monoxide in the Atmosphere.- 2.1. Introduction.- 2.1.1. Units of Measurement.- 2.1.2. Methods of Investigating the CO Content of the Atmosphere.- 2.1.3. Transfer of Trace Gases in the Atmosphere.- 2.2. Distribution of CO in the Atmosphere.- 2.2.1. Carbon Monoxide in Urban Areas.- 2.2.2. Distribution of CO in “Clean” Atmospheres.- 2.3. Variations of CO Content in the Atmosphere.- 2.3.1. Secular Trend of CO Content in the Atmosphere.- 2.3.2. Regular Temporal CO Variations in the Atmosphere.- 3. Abiogenic Processes in the CO Cycle.- 3.1. Anthropogenic CO Production.- 3.2. Natural Sources and Sinks of Atmospheric CO.- 3.2.1. Liberation of CO by Oceans.- 3.2.2. Photochemical Reactions in the Atmosphere.- 3.2.3. Liberation of CO from the Interior of the Earth.- 3.2.4. Other Geophysical Sources.- 4. Role of Biological Agencies in Forming and Binding CO.- 4.1. Formation of CO by Living Systems.- 4.1.1. Production of CO by Animals.- 4.1.2. Formation of CO by Algae and Cyanobacteria.- 4.1.3. Formation of CO by Higher Plants.- 4.1.4. Production of CO by Bacteria.- 4.1.5. Conclusion.- 4.2. Fixation of CO in the Biosphere.- 4.2.1. Reaction with Hemoproteins.- 4.2.2. Fixation of CO by Higher Plants.- 4.2.3. Absorption of CO by the Soil.- 4.2.4. Fixation of CO by Nonspecific Microflora.- 5. Carboxydobacteria.- 5.1. History of Research.- 5.2. Characteristics of the Physiological Group.- 5.2.1. Isolation of Carboxydobacteria.- 5.2.2. Morphological and Cultural Characteristics.- 5.2.3. Growth of Carboxydobacteria under Autotrophic Conditions.- 5.3. Utilization of CO by Carboxydobacteria.- 5.4. Conclusion.- 6. Comparative Role of Different Factors in the CO Cycle.- References.- 6 Microbial Ecology of the Human Skin.- 1. The Environment.- 1.1. Introduction.- 1.2. Physical Features.- 1.2.1. Hair.- 1.2.2. pH.- 1.2.3. Temperature.- 1.2.4. Humidity.- 1.3. Availability of Nutrients.- 1.3.1. Sweat.- 1.3.2. Antibacterial Substances.- 1.3.3. Studies on Sebum.- 1.4. Location of Skin Flora.- 1.5. Microbial Adherence to Skin.- 1.6. Recovery of Microbes from Skin.- 2. Cutaneous Microflora.- 2.1. Taxonomy of the Cutaneous Cocci.- 2.2. Micrococcaceae.- 2.3. Staphylococcus aureus.- 2.4. The Taxonomy of Skin Coryneforms.- 2.5. Aerobic Coryneforms.- 2.6. Anaerobic Coryneforms.- 2.7. Gram-Negative Bacteria.- 2.8. Yeasts—Pityrosporum.- 3. Microbes in Their Habitat.- 3.1. Host Factors.- 3.2. Microbial Coactions.- 3.3. Ecological Genetics.- 3.4. Experimental Ecological Studies.- References.