We have investigated mtDNAorganization in the o6mycetous water mold; Achlya, and report here that this primitive organism contains a circular mitochondrial genome of 49.8 kilobase, pairs. Extensive restriction endonuclease analysis indicates that a significant portion of the genome is present as an inverted repeat. Of 52 restriction sites for 14 enzymes. thus far mapped, 28 sites cluster in two 9.6-kilobase-pair regions; within these regions, the sequence of sites is inverted but the spacing between analogous sites is identical. The repeat arms have a maximum length of 12.1 kilobase pairs and are separated by 4.64.4 and 21.0-22.3 kilobase pairs of unique sequences. Transfer hybridization experiments show that genes for both the large and the small rRNAs are contained within each repeat. Restriction endonuclease analysis shows that the unique regions between the inverted repeats are present in both possible orientations with respect to each other and in approximately equal proportions. These orientational, or "flip-flop," isomers of the unique regions are postulated to occur by intramolecular homologous recombination between the repeated regions.Mitochondrial genomes, while functionally similar, present significant contrasts in gene structure and organization. Vertebrate mitochondrial genomes are circular with a length of about 16.4 kilobase pairs (kb) and a uniform gene order. However, ascomycetous fungi such as yeasts and Neurospora contain mtDNAs that vary in size, form, and organization and are up to five times larger (reviewed in refs. 1-3).Studies ofmitochondrial genes and gene organization among a small number of lower eukaryotes show a complex picture, with surprising differences among organisms. Some ofthe most striking contrasts are seen on comparing Saccharomyces cerevisiae with the related ascomycete Neurospora crassa. It has been known for several years that the ATPase subunit 9 gene is found on mtDNA in yeast (4) and on nuclear DNA in Neurospora (5). Recently, it has become clear that these organisms also use different mitochondrial genetic codes:-yeast uses the CUN series of codons (where N is any ribonucleotide) to represent threonine (6) and, like mammalian mitochondria (7, 8), uses AUA to code for methionine (9), while Neurospora uses CUN and AUA for leucine and isoleucine, respectively (10).Consequently, we have started to examine the mtDNA of other lower eukaryotes; here, we report the restriction map of mtDNA from the primitive oomycetous water mold Achlya ambisexualis. We find the unusual mitochondrial feature ofa large inverted repeat containing both rRNA genes. The population of molecules, moreover, contains two isomers that differ in the orientation of the unique regions with respect to each other. MATERIALS AND METHODSGrowth of Achlya. A. ambisexualis E-87 was obtained from W. Timberlake (University of California, Davis). Growth in PYG medium (11) was carried out at 300C on a Gyrotory shaker at 200 rpm from a spore inoculum (12). Mycelia were harvested in late logarithmicphase...

The Zoo National d'Abidjan (Abidjan Zoo) in Côte d'Ivoire, West Africa, holds the world's largest captive population of African slender-snouted crocodiles (Mecistops cataphractus, formerly Crocodylus cataphractus), at 36 adults, 16 yearlings, and 23 hatchlings. Twelve yearling and 12 adult slender-snouted crocodiles at the Abidjan Zoo were restrained for physical exam, body condition scoring, and venipuncture in September 2015. Blood samples collected from the supravertebral venous sinus were analyzed using a handheld blood analyzer (Abaxis® I-stat, Abaxis, Inc., Union City, California 94587, USA) with Chem8+ cartridges (CLIAwaived, Inc., San Diego, California 92130, USA). The adult crocodiles appeared in good general health and demonstrated blood values similar to those of other reptiles. The yearlings had low, ionized calcium values and low hematocrit and hemoglobin levels compared with the adult crocodiles and to other crocodile reference ranges. These findings may dramatically improve the health of the crocodiles and help to ensure a thriving captive population of this critically endangered species.